Introductory Essay, in Dr. Hooker's Flora of New 
Zealand: Yol. I.* 
Dr. J. D. Hooker, the Botanist of the Antarctic Expedition 
under Capt. Sir James C. Ross, on his return to England—com- 
bining with his own extensive collections and observations ali the 
accessible materials which have been accumulating in herbaria 
ever since the first voyage of Capt Cook—courageously assumed 
the task of preparing general floras of the three principal masses 
of southern land, in which his researches were made ; viz., Ant- 
arctic America, New Zealand, and Tasmania. The first of these 
undertakings was accomplished several years since, in the publi- 
cation of the Flora Antarctica; including Antarctic America 
with the Falkland Islands, the Campbell and Auckland Islands 
(properly pertaining to the New Zealand region), and the remote 
Kerguelen’s Land. Some abstracts were given in this Journal at 
the time, from parts of the work possessing a general interest. 
The recent completion of the fourth fasciculus, and first vol- 
ume, of the second work, viz. : the Flom Novce Zelandiat, com- 
prising all the Flowering plants of that group of islands, affords 
our author an opportunity to discuss, in an introductory essay, some 
topics of high interest to the philosophical naturalist; topics upon 
which his aptitude for such investigations, and the unparalleled 
opportunities of observation which he has enjoyed, and improved 
to the utmost, in almost every clime, must needs give no small 
weight to his opinions. Deeming as we do this essay to be an 
important and timely One, we propose to make a somewhat ex- 
tended analysis of it, leaving out of view for the present the body 
of the work, as interesting to the systematic botanist alone. 
In the Essay in question (occupying 39 quarto pages), Dr. 
Hooker gives, 1. The History of New Zealand Botany, and the 
probable limits of its flora. 2. An exposition of the views adopted 
in the descriptive part of the work, as to the affinities, limits, 
origjn, variation, distribution, and dispersion of plants generally. 
3. The illustration and development of these points by an analysis 
of the New Zealand Flora, and its relation to that of other countries. 
The history of the Botany of New Zealand, from the visit of 
Sir Joseph Banks and Dr. Solander, during Capt. Cook’s first voy- 
age, in 1790, down to the present time, need not arrest our 
attention. The actual number of species inhabiting these islands 
is a matter which it would be interesting to know, even approxi- 
mately. Dr. Hooker has brought together about 2,000 species in 
* The Botany of the Antarctic Yoyage of H. M. Discovery Ships Erebus and 
Terror, in the years 1839—1843, under the command of Capt. Sir James Clark 
Ross; by Joseph Dalton Hooker, M.D., etc. etc. II. Flora Novae-Zelandke, Parti. 
Flowering Plants. London. Lovell Reeve, 1852-1853. pp. 312, 4to, tab. 70. 
Am. Jour. Sci., Yol. XVII, No, 50. 2 
Notice of Dr. Hooker’s Flora of New Zealand. 
his Flora, including upwards of a hundred of the lower Crypto- 
gamia of which the materials are in too imperfect a state for 
satisfactory determination. This is more than double the number 
comprised in the latest preceding catalogue, that of M. Raoul, 
“who in 1846 enumerates only 920 species; which may be 
reduced to 770, if the naturalized and erroneous species be elimi- 
nated.” “ In 1838, Mr. Cunningham gave 640 species, which 
should be reduced to 570 : in 1832, M. Richard included 350 in 
his list: Forster’s Prodromus has 154; and Banks’ and Solati- 
der’s collections amount to 426. This rapid increase of the flora, 
which has thus been quintupled in twenty years, is mainly due to 
the attention which has been devoted to the lower orders. This 
may be easily shown ; for. whereas in all the earlier enumerations 
and collections the number of Flowering plants exceeds the Flow- 
erless, in M. Raoul’s catalogue they are equal, and in the present 
work the relative proportions are reversed ; the Phsenogamic 
plants being to the Cryptogamic as 1 to 16, i. e. about two to 
three.” As to the probable ratio of the known materials to the 
whole flora, Dr. Hooker remarks that “ the islands have been 
botanized upon by upwards of 35 individuals, whose specimens 
have (with a few unimportant exceptions) all passed under my 
eye. The flora of the Northern Island has been tolerably well 
examined, so far as its flowering plants are concerned; though 
there remains a good deal to be done on the west coast, especially 
in the neighborhood of Mount Egmont. Dr. Lyall alone has 
collected on the Southern Island, and on the west coast north of 
Dusky Bay. The Middle Island has been visited by few explorers ; 
its north and east coasts alone having been botanized : the west, 
and the whole mountain range require a careful survey ; and, con- 
sidering how many Auckland and Campbell Islands’ plants are 
still strangers to New Zealand, it cannot be doubted that much 
remains to be discovered there. Excepting from the above men- 
tioned tracts, 1 do not expect much novelty among Flowering 
plants, for the following reasons: 1. There is a remarkable 
sameness in the flora throughout large tracts, (in which respect 
New Zealand contrasts remarkably with Tasmania); 2. Because 
out of the 730 flowering plants known, there are scarcely one 
hundred that have not been gathered by several individuals; 
3. Because the collections I have lately received, though some of 
them are extensive, and from scarcely visited localities, yet con- 
tain little or no novelty. With Cryptogamia the case is widely 
different; and it is difficult to estimate the vast number, especially 
of Mosses, Hepaticae, and Fungi, that will reward future explor- 
ers in what, as far as Flowering plants are concerned, are exhaus- 
ted fields.” From the data now possessed, and from a comparison 
of the same with the flora of better known countries, Dr. Hooker 
ventures the opinion that there are not more than 4000 species in Notice of Dr. Hooker's Flora of Neio Zealand. 
3 
New Zealand, of which 1000 may be Flowering plants. l( Com- 
pared with any other countries in the same latitude, this is a very 
scanty flora indeed, especially as regards Flowering plants; of 
which Britain contains, in about the same area, upward of 1,400 
species; and in Tasmania, not yet well explored, and containing 
only one-third of the area, upwards of 1000 have already been 
discovered. In Cryptogamous plants, on.the other hand, these 
islands are extremely rich, not only proportionately to the 
Phasnogamic, but absolutely so. Great Britain, where the lower 
orders have been assidously studied for fifty years, contains about 
50 Ferns, and Tasmania 64;” while Dr. Hooker’s list of New Zea- 
land Ferns (including Lycopodiaceas), after reducing almost half 
as many nominal species to more varieties, contains upwards of 
1.14 species. The same result would appear all the more striking- 
ly on a comparison with any equivalent continental tract in the 
northern hemisphere. In all British America and Oregon only 
62 species of Ferns and Lycopodiaceae are recorded. 
Dr. Hooker’s second chapter, on the limits of species, their dis- 
persion and variation, deals with matters of higher general interest. 
To bring the points in question fairly into view, he assumes four 
positions as heads of the subjects upon which he proceeds to dis- 
course, namely : 
“ 1. That all the individuals of a species (as I shall attempt to 
confine the term) have proceeded from one parent (or pair), and 
that they retain their distinctive (specific) characters. 
2. That species vary more than is generally admitted to be the 
case. 
3. That they are also much more widely distributed than is 
usually supposed. 
4. That their distribution has been effected by natural causes ; 
but that these are not necessarily the same as those to which they 
are now exposed.” 
The first of these propositions should have been divided into 
two :—inasmuch as the first clause is not only open to some very 
specious if not cogent objections which do not apply to the others, 
but is from its very nature incapable of being supported by the 
kind of evidence which may sustain the other propositions. The 
fact that we constantly see like individuals reproduced, and under 
favorable circumstances increased, from a parent stock, lays, 
indeed, a solid ground for the inference that this process has been 
going on from the beginning : but how things go on, and how 
they began, are two different questions; and it is seldom, if ever, 
that the facts and deductions which account for the former, can 
be made to throw much direct light on the latter. Why is it not 
antecedently just as probable that several or many individuals of 
each species of plant, as identically like each other as are the 
offspring to the parent now, were created at the beginning, as 4 
Notice of Dr. Hooker’s Flora of New Zealand. 
that each began with a single pair? We would still maintain 
that the objective idea of species arises from this “ perennial 
succession of like individuals (to use the phrase of Linnaeus), 
sustaining to each other the relation of parent and progeny; and 
we think that the evidence on that side of the question strongly 
favors the inference, that plants, at least, have been distributed 
each species from a single and specific primordial area: but we 
know not what scientific evidence makes it needful to maintain 
the doctrine of the single creation of species in the restricted form 
of a single initial individual or pair. Were we even to go so far 
as explicitly to assume the likelihood, in certain cases, of the 
original creation of numerous individuals of a species, all alike 
in character, we could not be charged with infringing the rule 
that no more causes should be assumed than are requisite to 
ensure the result; since—to say nothing of the imminent risk 
of the premature destruction of a single individual—in many 
cases both of animals and vegetables, a considerable number 
would be required at the outset to fulfil the relations established 
between the individuals, either of the same or of different species. 
It would be more satisfactory, therefore, because less hypothetical 
and more within the reach of evidence, if the proposition were 
stated in the more general form ; viz., that all the individuals of 
a species have proceeded from a common stock, assigned to a 
limited primordial area;—in which form its bearing upon the 
other propositions would not be altered. Indeed, Dr. Hooker ex- 
pressly states, in the commencement of his remarks upon the first 
proposition, that he lays no stress upon that particular hypothesis, 
nor does he advance any arguments in support of it. The whole 
section is, in fact, mainly devoted to the illustration of the 
second clause, namely, that species retain their distinctive char- 
acters from age to age. As the section can hardly be abridged 
without injury, we extract a large portion of it. After stating 
various views that are maintained in respect to the origin or devel- 
opment of species, the author proceeds : 
“ Arguments in favor of these views are not wanting, derived both 
from the animal and vegetable kingdoms; the chief of which are 
drawn from a large class of well established facts, upon the bearings 
of which the most distinguished and candid naturalists are divided in 
opinion : such are—the great number of genera whose species have 
baffled all attempts at circumscription by fixed characters,—the facility 
with which breeds of certain plants and animals may be propagated, 
and the comparative certainty with which some few varieties are repro- 
duced under favorable circumstances,—the great facility with which 
many plants hybridize, and the facts of hybrids having proved fertile,— 
the sudden appearance and unexplained cause of many varieties or 
sports,—and the difficulty of accounting for the existence of plants and 
animals in two or more localities, between which they cannot have been Notice of Dr. Hooker's Flora of New Zealand. 
5 
transported by natural causes now in operation. These are all ques- 
tions relating to the diffusion and variation of species, which will be 
discussed here and in the following section. 
Arguments in favor of the single creation, and permanence of spe- 
cies, are all based upon general considerations of the phenomena of 
distribution. Comparative anatomy, which has thrown so great light 
upon this branch of study in the sister kingdom, has not done so much 
for plants ; this arises from several causes: 1. The habits of allied 
plants do not differ so remarkably as those of animals, and there is con- 
sequently less modification of their functional organs. 2. The relation 
of these modifications to the habits and wants of the species, is in the 
animal kingdom directly appreciable, but in plants no such connection 
can be traced.* 3. The individual organs of support, respiration, and 
reproduction, are infinitely more variable and susceptible of change and 
even obliteration1 in plants, without affecting the life either of the indi- 
vidual or of the species.t The result of these facts is that we have 
the means in animals of appreciating the extent and value of differen- 
ces, by combined observations upon structure and functions, upon hab- 
its and organization, which we have not in the vegetable kingdom, and 
which the phenomena of cultivation assure us do not exist to a degree 
that has, within the limits of our experience, proved available for throw- 
ing much light on the subject. 
The arguments in favor of a permanence of specific characters in 
plants are :— 
1. The fact that the amount of change produced by external causes 
does not warrant our assuming the contrary as a general law. Though 
there are many notorious cases in which cultivation and other causes 
produce changes of greater apparent value than specific characters 
generally possess, this happens in comparatively very few families, and 
only in such as are easily cultivated. In the whole range of the vege- 
table kingdom, it is difficult to produce a change of specific value, how- 
ever much we may alter conditions ; it is much more difficult to prevent 
an induced variety from reverting to its original state, though we perse- 
* The structure of woods offers many illustrations of this; very closely allied 
plants (especially Leguminosce) differing entirely in the nature, arrangement, and de- 
velopment of the vascular and cellular tissues of their trunks. Though to a great 
extent these differences accompany a habit of growth (as in the case of erect and 
scandent JBauhinias), there is nothing in the abnormally developed wood of the 
climbing Bauhinia that would lead a skilled physiologist ignorant of the fact to say 
that it was better adapted to a climbing than to an erect plant; the function is ex- 
perimentally known to be indicated by the structure, but the structure is not seen to 
be adapted to the function. This is not so in the sister kingdom, for we confidently 
pronounce an animal to be a climber, because we see that its organs are adapted to 
the performance of that function; here the habit is not only indicated by the struc- 
ture but the latter is explained by the function which it enables the animal to fulfill. 
f To ta,ke an extreme case of this;—many plants are known, in a wild and culti- 
vated state, which propagate abundantly by root or division, where they do not do so 
by seed. Anacharis Alsinastrum is a conspicuous example: it is a unisexual water- 
plant, of which one sex alone was introduced from North America into England, 
where it has within a few years so spread by division as to be a serious impediment 
to inland navigation. The Horse-radish is another example, it being, I believe, never 
known to seed or even to bear perfect flowers. A still more remarkable case has 
been pointed out to me by Mr. Brown, in the Acorus Calamus, a plant spread (not 
by cultivation) over the whole north temperate hemisphere, which bears hermaphro- 
dite flowers, but very rarely seeds. 6 
Notice of Dr. Hooker’s Flora of Next) Zealand. 
vere in supplying the original conditions; and it is most difficult of all 
to reproduce a variety with similar materials and processes.* 
2. In tracing widely dispersed species, the permanence with which 
they retain their characters strikes the most ordinary observer; and 
this, whether we take such plants as have been dispersed without the 
aid of man (as Sonchus oleraceus, Callitriche, and Montia) through 
all latitudes from England to New Zealand ; or such as have within 
modern times followed the migrations of man (as Poa annua, Phalaris 
Canariensis, Dock, Clover, Alsine media, Capsella bursa-pastoris, and 
a host of others); or such as man transports with him, whether such 
temperate climate plants as the cerealia, fruits, and flowers of the gar- 
den or field, or such tropical forms as Convolvulus Batatas and yams, 
which were introduced into New Zealand by its earliest inhabitants;— 
all these, in whatever climate to which we may follow them, retain the 
impress of their kind, unchanged save in a trifling degree. 
3. With comparatively few exceptions, plants are confined within 
well-marked limits, which, though often very wide, are sometimes as 
much the reverse ; while the instances are rare of sporadic species, as 
such are called which are found in small numbers in widely sundered 
localities. These facts seem incompatible on the one hand with the 
theory of species spreading from many centres, and on the other with 
their varying indefinitely; for were it otherwise, sporadic distribution 
would be the rule, insular floras would not necessarily be peculiar, and 
similar climates would have similar, if not identical species, which is 
not the case. 
4. A multitude of allied species of plants grow close together with- 
out any interchange of specific character; and there are instances of 
exceedingly closely allied plants keeping company under many modifi- 
cations of climate, soil, and elevation, yet never losing their distinctive 
marks. 
5. The individuals that inhabit the circumference of the area occu- 
pied by a species, are not found passing into other species, but ceasing 
more or less abruptly; their limits may meet or overlap those of one 
or more very similar species; when the individuals associate, but do 
not amalgamate. 
6. One negative argument in favor of distribution from one centre 
only, is, that taking the broadest view of the dispersion of species, we 
find that the more extensive familiest are more or less widely distribu- 
* I am quite aware that this argument will be met by many instances of change 
produced in our garden plants: but, after all, the skill of the gardener is successfully 
exerted in but few cases upon the whole: out of more than twenty thousand species 
cultivated at one time or another in the Royal Gardens of Kew, how few there are 
which do not come up not only true to their species, but even to the race or variety 
from which they spring; yet it would be difficult to suggest a more complete change 
than that from the Alps or Polar regions to Surrey, or from the free air of the trop- 
ics to the thoroughly artificial conditions of our hot-houses. Plants do not accom- 
modate themselves to these changes: either they have passive powers of resisting 
their effects to a greater or less degree, or they succumb to them. 
fThis rule does not extend to the Natural Orders themselves. The Composite, 
whose facilities for dispersion are proverbial, are amongst the most local; and the 
same may be said of Leguminosce and Solanece, whose seeds retain their vitality in 
a remarkable degree: a few of their species are remarkably cosmopolite, but the 
greater number have generally narrow ranges. Notice of Dr. Hooker's Flora of New Zealand. 
7 
ted, very much in proportion to the facilities they present for disper- 
sion. Thus the most minute-spored Cryptogams* are the most widely 
dispersed of all organized nature ; plants that resist the influence of 
climate best, range furthest; water-plants are more cosmopolite than 
land-plants, and inhabitants of salt, more than those of fresh water: 
the more equable and uniform is the climate of a tract of land, the 
more uniformly and widely will its plants be distributed. 
7. The species of the lowest orders are not only the most widely 
diffused, but their specific characters are not modified by the greatest 
changes of climate, however much their stature and luxuriance may 
vary. Fungi offer a remarkable instance of this: their microscopic 
spores are wafted in myriads through the air; the life of the individu- 
als is often of very short duration, and many of them being as sensitive 
as insects to temperature and humidity, they are ephemeral in all sen- 
ses; sometimes appearing only once in the same spot, and remaining 
but a few days, never to reappear within the observer’s experience'. 
The specific characters of many reside in the diameter, form, color, 
and arrangement of their most minute organs, whose analysis demands 
a refinement of microscopic skill ; yet the most accomplished and pro- 
found botanist in this Natural Order (who has favored me with the de- 
scriptions of the New Zealand Fungi) fails to find the most trifling 
character by which to separate many New Zealand species from 
ropean. 
8. The fact, now universally conceded by all intelligent horticultur- 
ists, that no plant has been acclimated in England within the experi- 
ence of man, is a very suggestive one, though not conclusive ; for it 
may be answered, that plants which cannot survive a sudden change, 
might a slow and progressive one. On the other hand, plants have 
powers of enduring change when self-propagated that they have not in 
our gardens; thus 1 find a great difference in the hardiness of individ- 
uals of several Himalayan plants,! depending upon the altitude at which 
they were gathered. In these cases the species is the same, and the 
parent individuals were not even varieties of one another, except so far 
as regards hardiness; in other words, the specific character remains 
unaltered in spite of the change of constitution, just as the climate of 
one part of the globe disagrees with the human race of another, and is 
even fatal to it. 
Such are a few of the leading phenomena or facts that appear to me 
to give the greatest weight to the opinion that individuals of a species 
are all derived from one parent: for such arguments as the New Zea- 
land Flora furnishes, I must refer my readers to the following chapter. 
I would again remind the student that the hasty adoption of any of 
these theories is not advisable: plants should be largely collected, and 
* The fact (first communicated to me by the Rev. M. J. Berkeley) of the spores 
of Fungi having been found by Professor Ehrenberg mingled with the atmospheric 
dust that has fallen on ships far out at sea, is one of the most decisive proofs of this. 
f Thus some of the seedling Pines whose parents grew at 12,000 feet appear har- 
dy, whilst those of the same species from 10,000 are tender. The common scarlet 
Rhododendron of Nepal and the Northwest Himalaya is tender, but seedlings of the 
same species from Sikkim, whose parents grew at a greater elevation, have proved 
perfectly hardy. 8 
Notice of Dr. Hooker's Flora of New Zealand. 
studied both in the living and dried states, and the result of their dis- 
section noted, without reference to any speculations, which are too apt 
to lead the inquirer away from the rigorous investigation of details, 
from which alone truth can be elicited. When however the opportunity 
or necessity arises for combining results, and presenting them in that 
systematic form which can aihne render them available for the purpo- 
ses of science, it becomes necessary for the generalizer to proceed 
upon some determinate principles.” 
The considerations here adduced bear partly in favor of the 
single creation of species of plants, partly on their permanence of 
specific characters from age to age ; which are different questions, 
although closely connected. In respect to the first, we have the 
mere statement of the nature and kind of evidence that is avail- 
able for the support of that doctrine : for its application to a par- 
ticular flora, by which its amount and weight may be tested, we 
are referred to a subsequent portion of the essay. So, likewise, 
as to the permanence of species, our general conclusions must 
needs depend upon a knowledge of the limits within which the 
same species may vary ; atopic which is discussed in the follow- 
ing section, mainly in view of its practical botanical applications. 
It were well that the considerations on which the doctrine of the 
single, as opposed to the double or multiple, origin of species rests, 
should be succinctly presented at one view, that their value may 
be estimated. For it is obvious that the very establishment of 
Dr. Hooker’s second and third propositions may react powerfully 
upon the first. If species generally are much “ more widely dif- 
fused than is usually supposed,” then the theory of the double or 
multiple origin of species, as maintained by Schouw and others, 
becomes all the more likely, at least until adequate natural means 
of dispersion are clearly shown. And if, at the same time, “species 
vary in a state of nature more than is usually supposed,” while 
what we term their specific characters are permanent, though the 
amount and value of these characters differs greatly in different 
species, then it may with the more probability be supposed that 
many of these differences were aboriginal. And these two infer- 
ences, taken together, would perhaps necessitate the conclusion, 
maintained we believe substantially by Prof. Agassiz, that species 
are ideal, as much so as genera, and even that they may have 
been represented from the beginning by as many individuals, and 
distributed over as wide an area, as at any subsequent time. A 
view which, by separating the idea of genetic connection from 
our conception of a species, seems to leave these no ground of 
objective reality to rest upon. We are reluctant to rest the very 
basis of natural history upon a priori conceptions, and therefore 
cling to the material view, that a species is not only “ a primordial 
form” (the definition of the late Dr. Morton), but one repre- 
sented in nature by the perennial succession of essentially like Notice of Dr. Hooker's Flora of New Zealand. 
9 
individuals, which sustain to each other the relation of parent 
and offspring, and which, as we may actually follow them onward 
from generation to generation, so we may mentally trace them 
backward to a common and probably local stock of homogeneous 
individuals, if not to a single individual or pair. This furnishes 
a common standard to which our empirical determinations of 
species may be referred, and the discordant views of different de- 
scribers be rendered commeasurable ; as it reduces the differences 
to questions of the probable value of characters in each particular 
case. For the fact must not be overlooked, that the greater part 
of the species characterized in our systematic works are only pro- 
visional determinations—more or less probable conclusions from 
incomplete data. 
Some valuable and timely remarks are to be found in the fol- 
lowing extract: 
“ It is not surprising that two naturalists, taking opposite views of the 
value of characters, should so treat a variable genus that their conclu- 
sions as to the limits of its species should be wholly irreconcilable. 
Some naturalists consider every minute character, if only tolerably con- 
stant or even prevalent, as of specific value ; they consider two or 
more doubtful species to be distinct till they are proved to be one ; they 
limit the ranges of distribution, and regard plants from widely severed 
localities as almost necessarily distinct; they do not allow for the ef- 
fects of local peculiarities in temperature, humidity, soil, or exposure, 
except they can absolutely trace the cause to the effect; and they 
hence attach great importance to habit, stature, color, hairiness, period 
of flowering, etc. These views, whether acknowledged or not, are 
practically carried out in many of the local floras of Europe, and by 
some of the most acute and observant botanists of the day ; and it is 
difficult to over-estimate the amount of synonymy and confusion which 
they have introduced into the nomenclature of some of the commonest 
and most variable of plants. In such hands the New Zealand genera 
Coprosma, Celmisia, Epilobium, etc., may be indefinitely extended. 
The principles I have adopted are opposed to these : I have based my 
conclusions on this subject upon a very extensive examination of living 
plants in all latitudes, with my attention particularly directed to the in- 
fluence of external causes, not only on the general phenomena of veg- 
etation, but also upon individuals. Added to this, I have paid a great 
deal of attention to variable plants, both of tropical and temperate cli- 
mates, and studied them in a living state, both wild and cultivated, and 
also in the herbarium. The result of my observations is, that differen- 
ces of habit, color, hairiness, and outline of leaves, and minute charac- 
ters drawn from other organs than those of reproduction, are generally 
fallacious as specific marks, being attributable to external causes, and 
easily obliterated under cultivation. It has hence been my plan to 
group the individuals of a genus which I assume after careful exami- 
nation to contain many species whose limits l cannot define, so that the 
species shall have the same relative value as those have of allied gen- 
era whose specific characters are evident. In doing so 1 believe I have 
Am. Jour. Sci., Yol. XVII.—1854. 10 
Notice of Dr. Hooker's Flora of New Zealand. 
followed the practice of every systemalist of large experience and ac- 
knowledged judgment since the days of Linnseus, as Bentham, Brown, 
the De Candolles, Deeaisne, Jussieu, Lindley, and the Richards; names 
which include not only the most learned systematists, but the most pro- 
found anatomists and physiologists. I am far from supposing that the 
same materials of a difficult group would receive precisely similar treat- 
ment at the hands of each of these eminent men ; but their results 
would so closely approximate as to be in harmony with each other, and 
available for scientific purposes: with all, the tendency would be to re- 
gard dubious species as varieties, to take enlarged views of the range 
and variation of species, and to weigh characters not only per se, but 
with reference to those which prevail in the order to which the species 
under consideration belong. 
In working up incomplete floras especially, I believe it to be of the 
utmost importance to adopt such a course, and to resist steadily the 
temptation to multiply names, for it is practically very difficult to ex- 
punge a species founded on an error of judgment or observation.* 
There is further an inherent tendency in every one occupied with spe- 
cialities to exaggerate the value of his materials and labors, whence it 
happens, that botanists engaged exclusively upon local floras are at is- 
sue with those of more extended experience, the former considering as 
species what the latter call varieties, and what the latter suspect to be 
an introduced plant the former are prone to consider a native. There 
is much to be said on both sides of such questions: the local botanist 
looks closer, perceives sooner, and often appreciates better, inconspicu- 
ous organs and characters, which are overlooked or loo hastily dis- 
missed by the botanist occupied with those higher branches of the sci- 
ence, which demand a wider range of observation and broader view* 
of specialities; and there is no doubt but that the truth can only be ar- 
rived at through their joint labors; for a good observer is one thing, 
and the knowledge and experience required to make use of facts for 
purposes of generalization, another ; minute differences however, when 
long dwelt upon, become magnified and assume undue value, and the 
general botanist must always receive with distrust the conclusions de- 
duced from a few species of a large genus, or from a few specimens 
of a widely distributed plant. 
I have been led to dwell at length upon this point, because I feel sure 
the New Zealand student will at first find it difficult to agree with me 
in many cases, as for instance on so protean a Fern as Lomaria pro- 
cera, whose varieties (to an inexperienced eye) are more dissimilar 
than are other species of the same genus. In this (and in many simi- 
lar cases) he must bear in mind that I have examined many hundred 
specimens of the plant, gathered in all parts of the south temperate 
hemisphere, and have found, after a most laborious comparison, that I 
could not define its charcters with sufficient comprehensiveness from a 
* The state of the British flora proves not only this, but further, that one such er- 
ror leads to many more of the like kind: students are led to over-estimate incon- 
stant characters, to take a narrow view of the importance and end of botany, and 
to throw away time upon profitless discussions about the difference between infi- 
nitely variable forms of plants, of whose identity really learned botanists have no 
doubt whatever. Notice of Dr. Hooker's Flora of New Zealand. 
11 
study of its New Zealand phases alone, nor understand the latter with- 
out examining those of Australia, South Africa, and South America. 
The resident may find two varieties of this and of many other plants, 
retaining their distinctive characters within his own range of observa- 
tion (for that varieties often do so* and for a very uncertain period, 
both when wild and also in gardens, is notorious), and he may perhaps 
have to travel far beyond his own island to find the link 1 have found, 
in the chain of forms that unites the most dissimilar slates of Lomaria 
procera; but he can no more argue thence for the specific difference 
of these, than he can for a specific difference between the aboriginal 
of New Zealand and himself, because he may not find intermediate 
forms of his race on the spot. We do not know why varieties should in 
many cases thus retain their individuality over great areas, and lose them 
in others; but the fact that they do so proves that no deductions drawn 
from local observations on widely distributed plants can be considered 
conclusive. To the amateur these questions are perhaps of very tri- 
fling importance, but they are of great moment to the naturalist who 
regards accurately-defined floras as the means for investigaline the 
great phenomena of vegetation ; he has to seek truth amid errors of 
observation and judgment, and the resulting chaos of synonymy which 
has been accumulated by thoughtless aspirants to the questionable honor 
of being the first to name a species.* 
There are many causes which render it extremely difficult to deter- 
mine the limits of species, and in some genera the obstacles appear to 
increase, the more the materials for studying them mulliply, and the 
more we follow our analysis of them into detail ; hence the botanist is 
often led on to an indefinite multiplication of species (with increased 
difficulty of determining those already established), or to a reduction of 
all to a few, or to one variable species. My own impression is, that 
the progress of botany points to the conclusion that in many genera we 
must ultimately adopt much larger views of the variation of species 
than heretofore, and that the number of supposed kinds of plants is (as 
I shall indicate elsewhere) greatly over-estimated ; if it be not so, we 
must either admit that species are not definable, or that there are hid- 
den characters throughout all classes of the vegetable kingdom, of 
which the botanist has no cognizance, and towards the acquirement of 
which, if they are ever to be revealed, all efforts in the direction in 
which we have been advancing appear to be vain. Could systematise 
as a body be accused of carrying out their investigations in an unphilo- 
sophical manner or spirit, or without due attention to all the modes of 
testing the validity of characters, afforded by the study of living and 
dried plants, by direct observation, and by experiment, there might be 
hopes ot such a revelation ; but such hopes are inconsistent with the 
great advances that have been made in systematic botany, which, hav- 
* The time however is happily past when it was considered an honor to be the 
namer of a plant; the botanist who has the true interests of science at heart, not 
only feels that the thrusting of an uncalled-for synonym into the nomenclature of 
science is an exposure of his own ignorance and deserves censure, but that a wider 
range of knowledge and a greater depth of study are required, to prove those dis- 
similar forms to be identical, which any superficial observer can separate by words 
and a name. 12 
Notice of Dr. Hooker's Flora of New Zealand. 
ing all tended to a more perfect knowledge of the affinities of plants, 
we are assured have been the effect of progress in the right direction.” 
Without doubt the preponderating tendency of the ablest and 
most experienced botanists of the present day is, to cancel nominal 
species, and, taking a more enlarged view of specific characters, 
to reduce slight or varying modifications to a common type ; a 
point not yet reached by zoologists, though probably it will be 
hereafter. Dr. Hooker’s tendency in this direction is evidently 
very decided ; possibly too much so. But it must be allowed 
that, while the botanists who multiply species unduly are always 
those who work upon scanty materials, or whose personal obser- 
vations are limited to a single district of country ; on the other 
hand, those who have access to the largest collections, or who 
have themselves botanized over various parts of the world, are for 
the most part as strongly inclined in the opposite direction. Now 
Dr. Hooker possesses both these advantages in an eminent de- 
gree. Young as he still is, no living botanist has investigated on 
the spot so many and so widely separated floras, and few like him 
have had constant access to the largest and best determined her- 
baria in the world. The principal danger here arises from 
Vembaras des richesses. It is hardly possible that a vast series of 
apparently confluent forms should receive the detailed examina- 
tion which the less privileged botanist may concentrate upon his 
fewer materials ; and much is left to the quick, almost intuitive 
judgment, which is liable to error, indeed, but in which the true 
genius of a botanist is generally disclosed. 
Perhaps there is no equally well known flora which compels 
the botanist to allow of such wide limits of variation in so large 
a proportion of its species, as that of New Zealand : at least so 
it would appear at first sight. Yet this character seems to be 
exhibited more or less by insular floras generally, in which a con- 
siderable number of the peculiar species are apt to be surprisingly 
polymorphous, as was remarked by Bory de St. Vincent half a 
century ago. 
Hybridization has been supposed by many to be an important 
element in confusing and masking species. Botanists of one 
class are apt to refer to its agency tlie unwelcome appearance of 
a specimen which combines two nominal species, founded on in- 
constant characters. Another class of naturalists appeal to the 
repeated occurrence of fertile hybrids, to negative the inference, 
otherwise unavoidable, that the production between two individ- 
uals of inherently fertile offspring, is a good reason for pronoun- 
cing them identical in species. Any continued effects from hybrid- 
ization in uncontrolled nature seem to be thoroughly guarded 
against in two ways ; first by the constitutional debility, if not by 
the invariable sterility of the hybrid offspring, rendering it of tran- 
sient duration ; and secondly, by the fact that, when prolific at Notice of Dr. Hooker's Flora of New Zealand. 
13 
all, they usually become so through fertilization by one or the 
other of the parents, when the offspring reverts to that specific 
type. Dr. Hooker justly remarks, that, 
“ As a general rule, the genera most easily hybridized in gardens 
are not those in which the species present the greatest difficulties. 
With regard to the facility with which hybrids are produced, the prev- 
alent ideas on the subject, are extremely erroneous. Grerlner, the most 
recent and careful experimenter, who appears to have pursued his 
inquiries in a truly philosophical spirit, says that 10,000 experiments 
upon 700 species produced only 250 true hybrids. It would have been 
most interesting had he added how many of them produced seeds, and 
how many of the latter were fertile, and for how many generations 
they were propagated. The most satisfactory proof we can adduce, of 
hybridization being powerless as an agent in producing species (how- 
ever much it may combine them), are the facts that no hybrid has ever 
afforded a character foreign to that of its parents, and that hybrids are 
generally constitutionally weak, and almost invariably barren. Uni- 
sexual trees must offer many facilities for the natural production of 
hybrids, which nevertheless have never been proved to occur; nor are 
such trees more variable than hermaphrodite ones.” 
May we not even say that they are less variable because uni- 
sexual, since their progeny is most likely to be originated from 
the conjunction of different trees, and individual peculiarities must 
needs be thereby blended and obliterated. When we consider 
how often it must happen that the ovules of one tree in an oak 
or pine forest are fertilized by the pollen of another; when we 
take into view the great number of unisexual plants, and consider 
also how many apparently hermaphrodite blossoms (far more than 
is generally supposed) are really submonoecious or polygamous, 
we may find reason to suspect in this a more general provision of 
nature for limiting congenital or induced individual forms than 
would at first appear. That some such controlling or amalga- 
mating agencies operate in nature may be inferred from a com- 
parison of the general homogeneity of an indigenous species, over 
even a large area, with the ready development of marked varie- 
ties or races in the case of every cultivated plant which is mul- 
tiplied from seed, and their perpetuation from generation to gen- 
eration, which is almost always ensured merely by cultivating 
each stock by itself. For the general law of nature is, not merely 
that species are true to their characters, these characters being 
rightly apprehended, but that the individual progeny inherits and 
transmits the special peculiarities of the parent or parents. Hence, 
that an isolated race retains certain characteristics so long as kept 
separate is no proof that it constitutes a species. Many a variety 
of recent and known origin does this. But, on the other hand, 
whatever individuals, however distinguished by minor differences 
when separate, are found to blend into a fertile race when associ- 
ated, must on sound principles be regarded as belonging to one 14 
Notice of Dr. Hooker1 s Flora of New Zealand. 
species. Perhaps if zoologists would contemplate the wide varia- 
tions presented by many plants of indubitably one and the same 
species, and the still wider diversities of long cultivated races 
from an original stock, they would find more than one instructive 
parallel to the case of the longest-domesticated of alt species, mail. 
Let it also be especially noted, that varieties are not always, 
not even generally, the result of external agencies, at least of 
such as we are able to detect. Certain varieties of plants are so 
originated: these are generally as transient as the cause that pro- 
duces them, and under altered circumstances often disappear even 
during the life of the individual: the plant may outgrow them. 
But others arise, we know not how. It is past the wit of man to 
trace a connection between the diverse forms of the foliage, &c. 
of a polymorphous plant such as a Coprosma, Metrosideros or 
Alseuosmia in New Zealand, and any difference of circumstances 
attributable to station ; still more so when these diversities occur 
side by side. Yet such are the varieties which ordinarily exhibit 
the greatest persistency, i. e. when kept from intermingling by 
mutual fecundation. What external circumstances can in the 
least account for the origin of the race of Dorking fowls, or 
Manx cats, or indeed of almost any of our domesticated races 
which were not produced by cross-breeding, that is by mingling 
the characters of two such races already in existence. Yet how 
certainly may we continue any of these races, under favorable 
circumstances, merely by maintaining the needful isolation ; and 
how soon would they mingle and disappear if they were left to 
themselves. Is not this equally true of the human races? 
From such facts, from the study of species remarkable for their 
polymorphous vegetation, as well as from the wide differences 
between certain domesticated races and their original stock,— 
differences not to have been expected on any known principles, 
and often far greater than those which are reckoned satisfactorily 
to mark the limits between other species,—the systematic bota- 
nist, at least, learns the lesson, that the amount of variation of 
which any one specific type is susceptible is only to be ascer- 
tained from observation and experience. 
Upon the third proposition, that “ Species are more widely 
diffused than is usually supposed,” our author’s statements are 
brief, but very decided and remarkable. He has already declared 
in the previous section “that it is by far the smaller half of the 
vegetable kingdom that is confined to narrow geographical or 
climatic areas, and that very few plants indeed are absolutely 
local; whilst the operations of the gardener and agriculturist prove 
that a vast proportion of the plants of the two temperate zones 
are capable of growing in any moderate climate.” “ I do not 
think,” he continues, “ that those who argue for narrow limits 
to the distribution and variation of species, can have considered Notice of Dr. Hooker’s Flora of New Zealand. 
15 
a garden in a philosophical spirit, or have weighed such facts as 
that there have been cultivated, within the last seventy years in 
the open air of England (at Kew), upwards of 20,000 species of 
plants from all quarters of the globe, and this within a space that, 
had it been left to nature, would not have contained 200 indige- 
nous species. The fact that an overwhelming proportion of 
these have come up true to their parent, and have continued so 
under every possible disadvantage of transportation and trans- 
plantation, of altered seasons, and amount and distribution of 
temperature and humidity, of unsuitable soil and exposure, and 
of the multitude of errors which unavoidable ignorance of their 
natural locality and habit engenders: such appears to me the 
most forcible argument in favor of the power of plants to retain 
their original characters under altered circumstances.” 
The validity of the last inference is unquestionable and valua- 
ble. As long as the plants survived, they doubtless retained their 
characters. Bat the value of the general statement, as respects 
its bearing upon the natural diffusion of species, depends much 
on the answer to the question, how long did the majority of the 
species survive. We should like to know how large a propor- 
tion continued beyond the first two or three years, even with all 
the advantages of being looked after by the gardener. 
But, returning to the general question, we remark, that there is 
little or no reason to expect a similarity between plants and ani- 
mals in this respect. From the nature of the case we should 
suppose that the latter, at least that land-animals, would be much 
more local than plants. 
We give to our readers the whole of the third section ; as 
some of the statements, especially those that relate to the proba- 
ble number of vegetable species known, are likely to excite some 
surprise. 
“This is a point upon which my own views differ materially from 
those of many of my fellow botanists, and which, if borne out by facts, 
leads to a widely different estimate of the number and variety of the 
members of the vegetable kingdom than that which is at present enter- 
tained. As with the affinities and variation of species, so is it with 
their distribution : an extensive knowledge of the subject is only to be 
obtained by actual observation over large areas, and many of them, or 
by the study and comparison of the contents of many museums. It 
has been my singular good fortune to have visited many regions of the 
globe, and to have entered into some details upon the dispersion of liv- 
ing species, which has always been a favorite pursuit of mine. I have 
further had the advantage of collating my results with the largest and 
best-named botanical collections in the w'orld, and have received a 
greater amount of assistance from my fellow naturalists than has fallen 
to the lot of most: facts which in ordinary cases are the result of long- 
study and much consultation have been placed at my disposal rather 
than worked out by myself. A very extended examination of these 
materials has only tended to confirm the view which originated in my 16 
Notice of Dr. Hooker's Flora of Neio Zealand. 
personal experience, viz., that the estimate of the number of species 
known to botanists is a greatly exaggerated one,* and the prevalent 
ideas regarding their distribution no less contracted. 
Many more plants are common to most countries lhan is supposed; 
I have found 60 New Zealand Flowering plants and 9 Ferns to be Eu- 
ropean ones, besides inhabiting various intermediate countries; and 
amongst the lower Orders we find a greatly increased proportion of 
species common to all countries: thus of Mosses alone 50 are found in 
New Zealand and Europe ;t of Hepatic® 13; of Algse 45 are also na- 
tives of European seas; of Fungi nearly 60; and of Lichens 100. 
So long ago as 1814 Mr. BrownJ drew attention to the importance of 
such considerations, and gave a list of 150 European plants common 
to Australia. The identity of many of these has repeatedly been 
called in question, but almost invariably erroneously; added to which 
more modern collectors have greatly increased the list. 
The too prevalent idea that the plants of newly discovered, isolated, 
or little visited localities must necessarily be new, has been a fertile 
source of the undue multiplication of species. There are very many 
cases of naturalists having been so impressed with this idea, that they 
have not thought it worth while to consult either books or herbaria be- 
fore describing the plants from such spots. The New Zealand Flora 
presents several instances of this; two conspicuous ones occur in the 
genus Oxalis ; one, O. corniculata, is amongst the most widely diffused 
and variable plants in the world ; of its varieties no less than seven or 
eight species have been made, most of them supposed to be peculiar to 
New Zealand ; not only is O. corniculala hence excluded from the 
flora, but, in the descriptions of these its varieties, no allusion is made 
to that plant.§ In the case of the other species the error is more ex- 
* According to the loose estimate of compilers, 100,000 is the commonly received 
number of known plants: from a multiplicity of data I can come to no other con- 
clusion but that half that number is much nearer the truth. This may well be con- 
ceived, when it is notorious that nineteen species have been made of the common 
Potato, and many more of Solatium nigrum alone. Pterin aquilina has given rise 
to numerous book species; Vernonia cinerea of India to fifteen at least. Many of 
the commonest European plants have several names in Europe, others in India, and 
still others in America, besides a host of garden names for themselves, their hybrids 
and varieties, all of which are catalogued as species in the ordinary works of refer- 
ence whence such estimates are compiled. 
f In fact the distribution of some Cryptogams is so wide, that I have visited a 
spot in a high southern latitude, nearly all whose plants are not only identical with 
those of Great Britain, but inhabit many intermediate temperate and tropical coun- 
tries. Cockburn Island, in lat. 64° 12' S. and long. 64° 49' W., nearly fulfills this 
condition; I thereon collected nineteen plants, of which three-fourths are natives of 
England. 
X Appendix to Flinders’s Voyage, vol. ii, p. 592. 
§ I have stated very confidently in the body of this work that eight of Cunning- 
ham’s and Richard’s species of this genus are all referable to one. This view will 
probably not meet the approbation of the local botanists, who will point to the con- 
stancy with which some of the states retain their characters under varied conditions. 
I value such facts very highly, and attach great weight to them, and did these vari- 
eties occur only in New Zealand I should perhaps have withheld so strong an opin- 
ion on the subject; but such is not the case. O. corniculata varies as much in nu- 
merous other parts of the world; and admitting, as every one must, that varieties 
are known to retain their characters with more or less constancy for certain periods, 
some other evidence is necessary to shake the opinion of the botanist who grounds 
his views on an examination of the plant from all quarters of the globe. Notice of Dr. Hooker's Flora of New Zealand. 
17 
cusable, and may be still open to question ;* it is that of O. Magellan- 
ica, originally discovered in Fuegia, and imperfectly described by Fors- 
ter, whose very indifferent specimens of it are in the British Museum. 
When re-found in New Zealand it was described as new, and called 
0. cataractce, and when found a third time in Tasmania, was called by 
still a third name, O. lactea. In this case a more important fact was 
smothered than that of the distribution of O. corniculata, namely, that 
of a very peculiar plant of the south temperate zone being common to 
these three widely sundered localities. 
Many similar instances might be added, for there are several New 
Zealand plants (as Pteris aquilina) that have a different name in almost 
every country in the world : and, partly from changes in nomenclature, 
partly from the reduction of species, I have found myself obliged to 
quote 1500 names for the 720 New Zealand Flowering plants described ; 
and I believe I might have doubled the number had my limits not 
obliged me to reduce the synonymy as much as possible ; in many ca- 
ses too much, I fear, for the requirements of working botanists in 
Europe.” 
One thing is clear, and important to be enforced : namely, that 
if determinations of species are to be of any value, especially in 
their bearing on general questions, they must rest solely upon 
observed characters of admitted value, irrespective of all theory. 
We pronounce such and such individuals, from a certain habitat, 
to belong to a distinct species, only because we find them pos- 
sessed of certain adequate distinctive marks. If we at length 
ascertain that particular species are peculiar to particular stations 
or parts of the world, we have a sound and valuable deduction. 
But to assume that certain plants, or certain animals, from widely 
sundered localities belong to different species, notwithstanding 
their resemblance, until the contrary is proved, and even to an- 
nounce this as a principle for general adoption, as has been done, 
is surely a gross instance of reasoning in a vicious circle. 
We cannot venture to condense, and therefore reproduce the 
whole of <§> 4, viz.: 
“ The distribution of species has been effected by natural causes, but. 
these arc not necessarily the same as those to which they are now ex- 
posed. 
Of all the branches of Botany there is none whose elucidation de- 
mands so much preparatory study, or so extensive an acquaintance 
with plants and their affinities, as that of their geographical distribution. 
Nothing is easier than to explain away all obscure phenomena of dis- 
persion by several speculations on the origin of species, so plausible 
that the superficial naturalist may accept any of them ; and to test their 
soundness demands a comprehensive knowledge of facts, which more- 
over run great risk of distortion in the hands of those who do not know 
* As no identification is proved till all the organs of the plants to be compared 
have been studied, there is yet a possibility of these three species proving distinct, 
but I do not at all expect it; the only difference I can find is a greater obliquity and 
emargination of the petals of the New Zealand species, but that character varies so 
much both in this plant and in others of the genus that it loses all specific value, 
Am. Jour, Sci., Vol. XVIL—1854. 8 18 
Notice of Dr. Hooker's Flora of New Zealand. 
the value of the evidence they afford. I have endeavored to enumer- 
ate the principal facts that appear to militate against the probability of 
the same species having originated in more places (or centres) than 
one; but in so doing I have only partially met the strongest argument 
of all in favor of a plurality of centres, viz., the difficulty of otherwise 
accounting for the presence in two widely sundered localities of rare 
local species, whose seeds cannot have been transported from one to 
the other by natural causes now in operation. To take an instance: 
how does it happen that Edwardsia grandiflora, inhabits both New 
Zealand and South America ? or Oxalis Magellanica both these local- 
ities and Tasmania? The idea of transportation by aerial or oceanic 
currents cannot be entertained, as the seeds of neither could stand ex- 
posure to the salt water, and they are too heavy to be borne in the air. 
Were these the only plants common to these widely-sundered localities, 
the possibility of some exceptional mode of transport might be admit- 
ted by those disinclined to receive the doctrine of double centres; but 
the elucidation of the New Zealand Flora has brought up many similar 
instances equally difficult to account for, and has developed innumera- 
ble collateral phenomena of equal importance, though not of so evident 
appreciation. These, which all bear upon the same point, may be ar- 
ranged as follows :— 
1. Seventy-seven plants are common to the three great south temper- 
ate masses of land, Tasmania, New Zealand, and South America. 
2. Comparatively few of these are universally distributed species, 
the greater part being peculiar to the south temperate zone. 
3. There are upwards of 100 genera, subgenera, or other well- 
marked groups of plants entirely or nearly confined to New Zealand, 
Australia, and extra-tropical South America. These are represented 
by one or more species in two or more of these countries, and they 
thus effect a botanical relationship or affinity between them ail, which 
every botanist appreciates. 
4. These three peculiarities are shared by all the islands in the south 
temperate zone (including even Tristan d’Acunha, though placed so 
close to Africa), between which islands the transportation of seeds is 
even more unlikely than between the larger masses of land. 
5. The plants of the Antarctic islands which are equally natives of 
New Zealand, Tasmania, and Australia, are almost invariably found 
only on the lofty mountains of these countries. 
Now as not only individual species, but groups of these, whether or- 
ders, genera, or their subdivisions, are to a great degree distributed 
within certain limits or areas, it follows that the flora of every island 
or archipelago presents peculiarities of its own. Though an insular 
climate may favor the relative abundance of individuals, and even spe- 
cies of certain Natural Orders, there is nothing in the climate, or in 
any other attribute of insularity, which indicates the nature of the pe- 
culiarity of endemic species. The islands of each ocean contain cer- 
tain botanically allied forms in common, which are more or less abund- 
ant in them, and rarely or never found on the neighboring continents; 
thus there are curious genera peculiar to the North Atlantic islands, 
others to the North Pacific islands, others to those of the South Pacific 
and others again to the Malayan Archipelago; just as there are still Notice of Dr. Hookers Flora of New Zealand. 
19 
others peculiar to the Antarctic islands, and many to New Zealand, 
Fuegia, and Tasmania. 
Each group of islands hence forms a botanical region, more or less 
definable by its plants as well as by its oceanic boundaries; precisely 
as a continuous area like Australia or South Africa does. There is 
however this difference, that whereas the Natural Orders that give a 
botanical character to a continuous area of a continent or to a~larcre 
island (as the Proteacece in South Africa or in New Holland, and Co- 
prosma in New Zealand) are numerous in species and often uniformly 
spread,—in clusters of small islands, distant from continents, they are 
few in species, and the individuals are scattered, appearing like the 
vestiges of a flora which belonged to another epoch, and which is pass- 
ing away. This is perhaps a fanciful idea, but one which I believe to 
contain the germ of truth ; for no Botanist can reflect upon the destruc- 
tion of peculiar species on small islands (such as is now going on in St. 
Helena amongst others), without feeling that, as each disappears, a gap 
remains, which may never be botanically refilled ; that not only are 
those links breaking by which he connects the present flora with the 
past, but also those by which he binds the different members of the 
vegetable kingdom one to another. It is not true in every sense that 
all existing nature appears to the naturalist as an harmonious whole ; 
each species combines by its own peculiarities two or more others more 
closely, and reveals their affinities more clearly, than any other does; 
just as the flora of an intermediate spot of land connects those of two 
adjacent areas better than any other locality does. It is often by one 
or a very few species that two large Natural Orders are seen to be re- 
lated ; just as by a few Chilian plants the whole flora of New Zealand 
is connected with that of South America. The destruction of a spe- 
cies must hence create an hiatus in our systems, and I believe that it is 
mainly through such losses that natural orders, genera, and species be- 
come isolated, that is, peculiar, in a naturalist’s eyes. 
To return to the distribution of existing species, I cannot think that 
those who, arguing for unlimited powers of migration in plants, think 
existing means ample for ubiquitous dispersion, sufficiently appreciate 
the difficulties in the way of the necessary transport. During my voy- 
ages amongst the Antarctic islands, I was led, by the constant recur- 
rence of familiar plants in the most inaccessible spots, to reflect much 
on the subject of their possible transport; and the conviction was soon 
forced upon me, that, putting aside the almost insuperable obstacles to 
trans-oceanic migration between such islands as Fuegia and Kerguelen’s 
Land, for instance (which have plants in common, not found else- 
where), there were such peculiarities in the plants so circumstanced, as 
rendered many of them the least likely of all to have availed them- 
selves of what possible chances of transport there may have been. As 
species they were either not so abundant in individuals, or not prolific 
enough to have been the first to offer themselves for chance transport, 
or their seeds presented no facilities for migration,* or were singularly 
perishable from feeble vitality, soft or brittle integuments, the presence 
of oil that soon became rancid, or from having a fleshy albumen that 
* Thus of the Composites, common to Lord Auckland’s Group, Fuegia, and Ker- 
guelen’s Land, none have any pappus (or seed-down) at all! Of the many species 
with pappus, none are common to two of these islands! 20 
Notice of Dr. Hooker's Flora of New Zealand. 
quickly decayed.* Added to the fact that of all the plants in the re- 
spective floras of the Antarctic islands those common to any two of 
them were the most unlikely of all to emigrate, and that there were 
plenty of species possessing unusual facilities, which had not availed 
themselves of them, there was another important point, namely, the 
little chance there was of the seeds growing at all, after transport. 
Though thousands of seeds are annually shed in those bleak regions, 
few indeed vegetate, and of these fewer still arrive at maturity. There 
is no annual plant in Kerguelen’s Land, and seedlings are extremely 
rare there ; the seeds, if not eaten by birds, either rot on the ground or 
are washed away ; and the conclusion is evident, that if such mortality 
attends them in their own island, the chances must be small indeed for 
a solitary individual, after being transported perhaps thousands of miles, 
to some spot where the available soil is pre-occupied. 
Beyond the bare fact of the difficulty of accounting by any other 
means for the presence of the same species in two of the islands, there 
appeared nothing in the botany of the Antarctic regions to support or 
even to favor the assumption of the double creation, and I hence dis- 
missed it as a mere speculation which, till it gained some support on 
philosophical principles, could only be regarded as shelving a difficul- 
ty; whilst the unstable doctrine, that would account for the creation of 
each species on each island by progressive development on the spot, 
was contradicted by every fact. 
It was with these conclusions before me, that I was led to speculate 
on the possibility of the plants of the Southern Ocean being the re- 
mains of a flora that had once spread over a larger and more continu- 
ous tract of land than now exists in that ocean ; and that the peculiar 
Antarctic genera and species may be the vestiges of a flora character- 
ized by the predominance of plants which are now scattered throughout 
the southern islands. An allusion to these speculations was made in 
the ‘Flora Antarctica1 (pp. 210 and 368), where some circumstances 
connected with the distribution of the Antarctic islands were dwelt 
upon, and their resemblance to the summits of a submerged mountain 
chain was pointed out; but beyond the facts that the general features 
of the flora favored such a view, that the difficulties in the way of trans- 
port appeared to admit of no other solution, and that there are no lim- 
its assignable to the age of the species that would make their creation 
posterior to such a series of geological changes as should remove the 
intervening land, there was nothing in the shape of evidence by which 
my speculation could be supported. I am indebted to the invaluable 
labors of Lyell and Darwin,! for the facts that could alone have given 
* Of the seeds sent to England from the Antarctic regions, or transported by my- 
self between the several islands, almost all perished during transmission. 
•(■ See Darwin’s ‘ Journal of a Naturalist,’ and ‘ Essays on Volcanic. Islands and Co- 
ral Islands.’ The proofs of the coasts of Chili and Patagonia having been raised 
continuously, for several hundred miles, to elevations varying between 400 and 1300 
feet, since the period of the creation of existing shells, will be found in the first- 
named of these admirable works, which should be in the hands of every New Zea- 
land Naturalist, if only from its containing important observations on his own isl- 
ands. The fact of this accomplished Naturalist and Geologist having preceded me 
in the investigation of the Natural History of the Southern Ocean, has materially 
influenced and greatly furthered my progress; and I feel it the more necessary to Notice of Dr. Hooker's Flora of Nevj Zealand. 
21 
countenance to such an hypothesis ; the one showing that the necessary 
time and elevations and depressions of land need not be denied ; and 
the other, that such risings and sinkings are in active progress over 
large portions of the continents and islands of the southern hemisphere. 
It is to the works of Lyell* that I must refer for all the necessary data 
as to the influence of climate in directing the migration of plants and 
animals, and for the%vidence of the changes of climate being depend- 
ent on geological change. In the ‘ Principles of Geology’ these laws 
are proved to be of universal application, and amply illustrated by their 
being applied to the elucidation of difficult problems in geographical 
distribution. It follows from what is there shown, that a change in the 
relative positions of sea and land has occurred to such an extent, since 
the creation of still existing species, that we have no right to assume 
that the plants and animals of two given areas, however isolated by 
ocean, may not have migrated over pre-existing land between them. 
This was illustrated by an examination of the natural history of Sicily 
(where land-shells, still existing in Italy, and which conlcj not have 
crossed the Straits of Messina, are found imbedded on the flanks of 
Etna high above the sea-level), regarding which Sir Charles Lyell states 
that most of the plants and animals of that island are older than the 
mountains, plains, and rivers they now inhabit.f 
It was reserved for Professor Edward Forbes, one of the most, ac- 
complished naturalists of his day, to extend and enlarge these views, 
and to illustrate by their means the natural history of an extensive 
area ; which he did by applying a profound knowledge of geology and 
natural history to the materials he had collected during his arduous sur- 
veys of many of the shores of Europe and the Mediterranean. The 
result has been the enunciation of a theory, from which it follows that 
the greater part, if not ail, of the animals and plants of ihe British 
Islands have immigrated at different periods, under very different cli- 
matic conditions; and that all have survived immense changes in the 
mention this here, because Mr. Darwin not only directed my earliest studies in the 
subjects of the distribution and variation of species, but has discussed with me all 
the arguments, and drawn my attention to many of the facts which I have endeav- 
ored to illustrate in this Essay. I know of no other way in which I can acknowl- 
edge the extent of my obligation to him, than by adding that I should never have 
taken up the subject in its present form, but for the advantages I have derived from 
his friendship and encouragement. 
* To Sir Charles Lyell’s works, indeed, I am indebted for the enunciation of those 
principles that are essential to the progress of every naturalist and geologist; those, 
I mean, that affect the creation and extinction, dispersion and subsequent isolation of 
organic beings; and though botanists still differ in opinion as to the views he enter- 
tains on the most speculative of subjects (the origin and permanence of species), 
there is, I think, but one as to the soundness and originality of his observations on 
all that relates to the strict dependence of organic beings on physical conditions in 
the state of the earth’s surface. I feel that I cannot over-estimate the labors of this 
great philosopher, when I reflect that without them the science of geographical dis- 
tribution would have been with me little beyond a tabulation of important facts; 
and that I am indebted to them, not only for having given a direction to my studies 
in this department, but for an example of admirable reasoning on the facts he has 
collected regarding the distribution of plants and animals. I have no hesitation in 
recommending the ‘ Principles of Geology’ to the New Zealand student of Nature, 
as the most important work he can study. 
j- See the Principles of Geology, ed. 9, p. 702, and Address to the Geological So- 
ciety of London by the President (Leonard Horner, Esq.), in 1847, p. 66. 22 
Notice of Dr. Hooker's Flora of New Zealand. 
configuration of the land and seas of Northern Europe. The argu- 
ments which support this theory are based upon evidence derived from 
Zoology and Geology,* and they receive additional weight from the fact 
that the distribution of British plants is in accordance with its principal 
features, t 
The geographical distribution of British plants has been the subject 
of the most rigorous investigation by one of our aBlest British botanists, 
Mr. FI. C. VVatson, who first drew attention to the various botanical 
elements of which the flora is composed, and grouped the species inlo 
botanical provinces. These provinces were intended for ‘showing the 
areas of plants, as facts in nature independent of all theoretical expla- 
nations and reasons.’ (Cybele Britannica, vol. i, p. 18). An inspec- 
tion of them shows the relations borne by the plants of England to 
those of certain parts of Europe and of the Arctic regions; and Pro- 
fessor Forbes, applying a modification of these botanical provinces to 
the illustration of his views of the original introduction of plants into 
the British Islands, proceeds to show that their migration took place at 
different periods, contemporary of course with the connection by land 
of each botanical region of Britain with that part of the continent which 
presents a similar association of plants. 
To extend a theoretical application of these views to the New Zea- 
land Flora, it is necessary to assume that there was at one time a land 
communication by which the Chilian plants were interchanged ; that at 
the same or another epoch the Australian, at a third the Antarctic, and 
at a fourth the Pacific floras were added to the assemblage. It is not 
necessary to suppose that for this interchange there was a continuous 
connection between any two of these localities, for an intermediate land, 
peopled with some or all of the plants common to both, may have ex- 
isted between New Zealand and Chili when neither of these countries 
was as yet above water.f To account, however, for the Antarctic 
* For the contents of the Essay itself, I must refer to the Records of the Geolog- 
ical Survey of Great Britain, vol. i, p. 336. This is the most original and able essay 
that has ever appeared on this subject, and though I cannot subscribe to all its bo- 
tanical details, I consider that the mode of reasoning adopted is sound, and of uni- 
versal application. What I dissent from most strongly is, the origin of the gulf- 
weed, the peopling of Scotch mountains by iceberg transport of seeds, and the too 
great stress laid upon the west Irish flora, whose peculiarities appear to me to be 
considerably over-esti mated. 
I It may be well to state to the New Zealand student, that there are no reasons 
to suppose that Botany can ever be expected to give that direct proof of plants 
having survived geological changes of climate, sea, and land, which animals do ; the 
cause is evident, for the bones of quadrupeds, shells of mollusca, and hard parts of 
many animals, afford an abundant means of specific identification, and such are pre- 
served when the animals perish. In plants the case is widely different: their perish- 
able organs of reproduction, which alone are available for systematic purposes, are 
seldom imbedded, even when other parts of the plants are. 
4 This disappearance of old land, and the migration of its flora and fauna to new, 
may be illustrated to a certain extent by the delta of any New Zealand river. A 
mud-bank on one shore, covered with mangroves, advances across the channel, the 
mangroves growing on the new land as it forms. The current changes, and the end 
of the bank (with its mangroves) is cut off, and becomes an island: another change 
of the river channel fills up that between the islet and the opposite shore, to which 
it hence becomes a peninsula, peopled by mangroves, whose parents grew on the 
opposite bank. Here, be it remarked, no subsidence is required, such as must have 
operated in the assumed isolation of New Zealand. Notice of Dr. Hooker's Flora of New Zealand. 
23 
plants on the lofty mountains, a new set of influences is demanded ; no 
land connection between these islands and New Zealand could have 
effected this, for the climate of the intermediate area must necessarily 
have prevented it. But changes of relation between sea and land in- 
duce changes of climate, and the presence of a large continent con- 
necting the Antarctic islands would, under certain circumstances render 
New Zealand as cold as Britain was during the glacial epoch. Sir C. 
Lyell first demonstrated this, and showed what such conditions should 
be; and by consulting the ‘ Principles of Geology,’ my reader will un- 
derstand how such a climate would reign in the latitude of New Zea- 
land, as that its flora should consist of what are now Antarctic forms of 
vegetation. The retirement of the plants to the summit of the New 
Zealand mountains,* would be the necessary consequence of the ame- 
lioration of climate that followed the isolation of New Zealand, and the 
replacement of the Antarctic continent by the present ocean. 
The climate throughout the south temperate zone is so equable, and 
the isothermal lines are so parallel to those of latitude, that it is not 
easy for the New Zealand naturalist to realize the altered circumstan- 
ces that would render the plains of his island suitable for the growth of 
plants that now inhabit its mountains only;f but if he glance at the 
map of the isothermal lines of the northern hemisphere, he wiil see 
how varied are the climates of regions in the same latitude ; that Lon- 
don, with a mean temperature of 51°, is in the same latitude as Hud- 
son’s Bay, where the mean temperature is 30°, and the soil ever fro- 
zen : and he will further be able to understand by a little reflection, 
how a change in the relative positions of sea and land would, by 
isolating Labrador, raise its temperature 10°-15°, causing the de- 
struction of all the native plants that did not retire to its mountain- 
tops, and favoring the immigration of the species of a more genial 
climate. 
The first inference from such an hypothesis is that the Alpine plants 
of New Zealand, having survived the greatest changes, are its most 
ancient colonists; and it is a most important one in many respects, but 
especially when considered with reference to the mountain floras of the 
* With regard to the British mountains, Professor Forbes imagines that they were 
islets in the glacial ocean, and received their plants by transportation of seeds with 
soil, on ice from the Arctic regions. This appears to me to want support, and there 
is much in the distribution of Arctic plants especially, wholly opposed to the idea 
of ice transport being an active agent in dispersion. A lowering of 10° of mean 
temperature would render the greater part of Britain suitable to the growth of 
Arctic plants; it would give it the climate of Labrador, situated in the same lati- 
tude on the opposite side of the Atlantic. Britain is the warmest spot in its lat- 
itude, and a very slight geological change would lower its mean temperature many 
degrees. 
f The New Zealand naturalist has probably a very simple means of determining 
for himself whether his island has been subject to a geologically recent amelioration 
of climate; to do which, let him examine the fiord-like bays of the west coast of 
the Middle Island, for evidence of the glaciers which there exist in the mountains 
having formerly descended lower than they now do. Glaciers to this day descend 
to the level of the sea in South Chili, at the latitude of Dusky Bay; and if they 
have done so in the latter locality, they will have left memorials, in the shape of 
boulders, moraines, and scratched and polished rocks. 24 
Notice of Dr. Hooker's Flora of New Zealand. 
Pacific and southern hemisphere generally. These may be classed 
under three heads :*— 
1. 'f'hose that contain identical or representative species of the Ant- 
arctic Flbra, and none that are peculiarly Arctic; as the Tasmanian 
and New Zealand Alps.t 
2. Those that contain, besides these, peculiarities of the Northern 
and Arctic Floras ;J as the South American Alps. 
3. Those that contain the peculiarities of neither; as the mountains 
of South Africa and the Pacific Islands. 
We thus observe that the want of an Arctic or Antarctic Flora at all 
in the Pacific islands, and the presence of an Arctic one in the Ameri- 
can Alps, are the prominent features; and 1 shall confine my remarks 
upon these to the fact that, with regard to the isolated islands of the 
Pacific, they are situated in too warm a latitude to have had their tem- 
perature cooled by changes in the relative position of land and ocean, 
so as to have harbored an Antarctic vegetation. With regard to the 
South American Alps, there is direct land communication along the 
Andes from Arctic to Antarctic regions ; by which not only may the 
strictly Arctic genera and species have migrated to Cape Horn, but by 
which many Antarctic ones may have advanced northward to the 
equator.§ 
There is still another point in connection with the subject of the rel- 
ative antiquity of plants, and in adducing it I must again refer to the 
‘ Principles of Geology,1 where it is said, ‘ As a general rule, species 
common to many distant provinces, or those now found to inhabit many 
distant parts of the globe, are to be regarded as the most ancient . . . . 
their wide diffusion shows that they have had a long time to spread 
themselves, and have been able to survive many important changes in 
Physical Geography.’|| If this be true, it follows that, consistently with 
the theory of the antiquity of the Alpine flora of New Zealand, we 
should find amongst the plants common to New Zealand and the Ant- 
arctic islands, some of the most cosmopolitan ; and we do so in Montia 
* I need scarcely remind my reader that in thus sketching the characteristics of 
these Alpine floras, I make no allusion to exceptions that do not alter the main fea- 
tures. I am far from asserting that there are no peculiar Arctic or Antarctic forms 
in the Pacific Islands, nor any peculiarly Arctic ones in Tasmania and New Zealand: 
but if, on the one hand, future discoveries of such shall weaken the points of differ- 
ence between these three mountain regions, on the other they might be very much 
strengthened by adducing the number of Arctic species common to the South Amer- 
ican Alps, but not found in the others. 
f These Antarctic forms are very numerous; familiar ones are Accena, Drapetes, 
Donatia, Gunnera, Oreomyrrhis, Lagenophora, Forstera, Ourisia, Fagus, Callixene, 
AsteHa, Gaimardia, A/epyrum. Orcobol.us, Carpha, Uncinia. 
\ Berberis, Sisymbrium, Thlaxpi, Arabia, Draba, Sagina, Lychnis, Cerastium, Fra- 
garia, Lathyrus, Vicia, Hippuris, Chrysoplenium, Ribes, Saxijraga, Valeriana, Aster, 
Hieracium, Stachys, Primula, Anagallis, Pinguicula, Statice, Empetrum, Phleum, 
Elymus, Hordeum. 
§ Why these Antarctic forms have not extended into North America, as the Arc- 
tic ones have into South America, is a curious problem, and the only hypothesis that 
suggests itself is derived from the fact that though the Panama Andes are not now 
sufficiently lofty for the transit of either, there is nothing to contradict the supposi- 
tion that they may have had sufficient altitude at a former period, and that one 
which preceded the advance of the Antarctic species to so high a northern latitude. 
| Principles of Geology, ed. 9, p. 702. Notice of Dr. HookeEs Flora of New Zealand. 
25 
font ana, Callitriche verna, Cardamme hirsuta, Epilohium telragonum, 
and many others. 
On the other hand, it must be recollected that there are other causes 
besides antiquity and facility for migration, that determine the distribu- 
tion of plants; these are their power, mentioned above, of invading 
and effecting a settlement in a country preoccupied with its own spe- 
cies, and their adaptability to various climates : with regard to the first 
of these points, it is of more importance than is generally assumed, and 
I have alluded to its effects under Sonchus, in the body of this work; 
As regards climates, the plants mentioned above seem wonderfully in- 
different to its effects.* 
Again, even though we may safely pronounce most species of ubiq- 
uitous plants to have outlived many geological changes, we may not 
reverse the position, and assume local species to be amongst the most 
recently created ; for whether (as has been conjectured) species, like 
individuals, die out in the course of time, following some inscrutable 
law whose operations we have not yet traced, or whether (as in some 
instances we know to be the case) they are destroyed by natural causes 
(geological or others), they must in either case become scarce and lo- 
cal while they are in process of disappearance. 
In the above speculative review of some of the causes which appear 
to affect the life and range of species in the vegetable kingdom, 1 have 
not touched upon one point, namely, that which concerns the original 
introduction of existing species of plants upon ihe earth. I have as- 
sumed that they have existed for ages in the forms they now retain, 
that assumption agreeing, in my opinion, with the facts elicited by a 
survey of all the phenomena they present, and, according to the most 
eminent zoologists, with those laws that govern animal life also; but 
there is nothing in what is assumed above, in favor of the antiquity of 
species and their wide distribution, that is inconsistent with any theory 
of their origin that the speculator may adopt. My object has not so 
much been to ascertain what may, or may not, have been the original 
condition of species, as to show that, granting more scope for variation 
than is generally allowed, still there are no unassailable grounds for 
concluding that they now vary so as to obliterate specific character; in 
other words, I have endeavored to show that they are, for all practical 
purposes of progress in botanical science, to be regarded as perma- 
nently distinct creations, which have survived great geological changes, 
and which will either die out, or be destroyed, with their distinctive 
marks unchanged. We have direct evidence of the impoverishment 
of the flora of the globe, in the extinction of many most peculiar insu- 
lar species within the last century ; but whether the balance of nature 
is kept up by the consequent increase of the remainder in individuals, 
or by the sudden creation of new ones, does not appear, nor have we 
any means of knowing: if the expression of an opinion be insisted on, 
* Mr. Watson (Cybele Britannica) gives the range of Callitriche in Britain alone 
as including mean temperatures of 40° to 52°, anil as ascending from the level of 
the sea to nearly 2000 feet in the East Highlands of Scotland. Montia, according 
to the same authority, enjoys a range of 86° to 52°, and ascends to 3300 feet; Epi- 
lobium, a temperature of 40° to 51°, and ascends to 2000 feet; Cardamme, a tem- 
perature of 37° to 52°, and ascends to 3000 feet. 
Am. Jour. Sci., Vol. XVII.—1854. 4 26 
Notice of Dr. Hooker's Flora of New Zealand. 
I should be induced to follow the example of an eminent astronomer, 
who, when the question was put to him, as to whether the planets are 
inhabited, replied that the earth was so, and left his querist to argue 
from analogy. So with regard to species, we know that they perish 
suddenly or gradually, without varying into other forms to lake their 
place as species, from which established premiss the speculator may 
draw his own conclusions. * * * 
To those who may accuse me of giving way to hasty generalization 
or loose speculation on the antiquity and dispersion of plants over parts 
of the Southern Hemisphere, l may answer, that no speculation is idle 
or fruitless, that is not opposed to truth or to probability, and which, 
whilst it co-ordinates a body of well established facts, does so without 
violence to nature, and with a due regard to the possible results of fu- 
ture discoveries. I may add, that after twelve years’ devotion to the 
laborious accumulation and arrangement of facts in the field and closet, 
untrammelled by any theories to combat or vindicate, 1 have thought 
that I might bring forward the conclusions to which my studies have 
led me, with less chance of incurring such a reproach, than those 
would, who with far better abilities and judgment, have not had my ex- 
perience and opportunities.” 
The hypothesis that these insular floras are the remains of 
larger floras greatly reduced or verging to extinction, will be found 
remarkably applicable, if we mistake not to the case of the 
Sandwich Islands; many of the characteristic species of which 
appear to be represented by comparatively few individuals, as if 
waning to extinction along with the Hawaian race. 
The general idea here so ably set forth by Dr. Hooker, in re- 
spect to the Antarctic and South Pacific floras, is a very important 
one, and worthy of the most extended and critical examination. 
Its establishment, moreover, by satisfactory evidence, would de- 
stroy one of the strongest grounds upon which the doctrine of 
the multiple origin of species (at least in the form maintained by 
Schouw) is supported. To complete the view, and fairly to exhibit 
the grounds upon which these theoretical conclusions are based, 
we should embrace in our extracts a large part of the remaining 
chapter; on the physiognomy and affinities of the New Zealand 
Flora, and on the variation of New Zealand species. But the 
necessary limits of our article forbid. A few facts regarding the 
more striking peculiarities of the New Zealand flora may be col- 
lected, The large proportion, both relatively and absolutely, of 
the Cryptogamia, and especially of Ferns, has already been noted. 
“ A paucity of Grasses, and absence of Leguminosae, and abun- 
dance of bushes and Ferns, and a want of annual plants, are the 
prevalent features of the open country ; whilst the forests abound 
in Cryptogamia, in Phsenogamic plants with obscure and green 
flowers, and very often of obscure and little known natural orders.” 
The number of natural orders of the Phaenogamic plants is 
remarkably large in proportion to the genera, even for an insular 
flora j being 92 to 282, or about one to three : while the genera Notice of Dr. Hooker's Flora of Neiv Zealand. 
27 
are to the species as 282 to 730, each genus having on the aver- 
age only species: so that the species average but eight for 
each order. This makes it one of the most difficult floras in the 
world for a beginner, who must know a natural order for every 
eight species. How recondite, vague, and unsatisfactory the na- 
tural system of Botany must appear to the New Zealand student ! 
Of the largest natural orders, as respects the number of spe- 
cies, the individuals are often so few that none of them form 
prominent features in the landscape. The Coniferce prove to 
be the most prevalent family; but the majority of their species 
are not social but grow intermixed with the trees, so as to give no 
character to the landscape ;—a case just opposite to what occurs 
in the northern hemisphere, at least in North America, where the 
species are few, but mostly social, and existing in a vast number 
of individuals, which often occupy considerable tracts almost 
exclusively, and thus strikingly impress their features upon the 
landscape. 
The number of kinds of trees is very large in proportion to 
the herbaceous plants; as there are 1.13 Phsenogamous trees, in- 
cluding shrubs above twenty feet high, or one-sixth of the flora, 
while in England there are not more than 35 native trees, in a 
much larger flora. 
A remarkably large proportion of the Phsenogamous flora of 
New Zealand consists of absolutely peculiar plants: of these 
there are 26 genera and 507 species ; or more than two-thirds of 
the whole. The greater part of these are Exogens. Of the 
remaining third, consisting of plants common to New Zealand 
and other countries: 
“ 193 species, or nearly one-fourth of the whole, are Australian. 
89 species, or nearly one-eighth of the whole, are South 
American. 
77 species, or nearly one-tenth of the whole, are common 
to both the above. 
60 species, or nearly one-twelvth of the whole, are European. 
50 species, or nearly one-sixteenth of the whole, are An- 
tarctic Islands, Fuegian, &c.” 
These several elements in the New Zealand flora, whether as 
represented by identical or cognate species, are in turn subjected 
to a critical analysis. The following extract, respecting the Aus- 
tralian element, is interesting from its direct bearing on the ques- 
tion of transport by water. 
“If the number of plants common to Australia and New Zealand is 
great, and quite unaccountable for by transport, the ahsence of certain 
very extensive groups of the former country is still more incompatible 
with the theory of extensive migration by oceanic or aerial currents. 
This absence is most conspicuous in the case of Eucalypti, and almost 
every other genus of Myrtacecc, of the whole immense genus of Acacia, 28 
Nolice of Dr. Hooker’s Flora of Nero Zealand. 
and of its numerous Australian congeners, with the single exception of 
Clianthus, of which there are but two known species, one in Australia, 
and the other in New Zealand and Norfolk Island. 
The rarity of Proteacece, Rulacece, and Slylidece, and the absence of 
Ccisucirina. and Callitris, of any Goodenice but G. littoral is (equally 
found in South America), of Tremandrece, Dilleniacetz, and of various 
genera of Monocotyledon.es, admit of no explanation consistent with 
migration over water having introduced more than a very few of the 
plants common to these tracts of land. Considering that Eucalypti 
form the most prevalent forest feature over the greater part of South 
and East Australia, rivalled by the Leguminosce alone, and that both 
these Orders (the latter especially) are admirably adapted constitution- 
ally for transport, and that the species are not particularly local or 
scarce, and grow well wherever sown, the fact of their absence from 
New Zealand cannot be too strongly pressed on the attention of the bo- 
tanical geographer; for it is the main cause of the difference between 
the floras of these two great masses of land being much greater than 
that between any two equally large contiguous ones on the face of the 
globe. If no theory of transport will account for these facts, still less 
will any of variation ; for of the three genera of Leguminosce. which do 
inhabit New Zealand, none favor such a theory ; one, Clianthus, I have 
just mentioned ; the second, Edwardsia, consists of one tree, identical 
with a Juan Fernandez and Chilian one, and unknown in New Hol- 
land ; and the third genus (Carmichcelia) is quite peculiar, and consists 
of a few species feebly allied to some New Holland plants, but exceed- 
ingly different in structure from any of that extensive Natural Order.” 
Dr. Hooker then appends a carefully prepared table of 228 
phaenogamous species which may be said to represent each other 
in two or all the three South temperate masses of land, viz., New 
Zealand (including Auckland and Campbell’s Islands), Australia 
(including Tasmania), and extra-tropical South America, inclu- 
ding the Falkland Islands ; the list being confined to cases of 
real and usually very close botanical affinity, to the exclusion of 
analogical resemblances, however striking. The list is by no 
means overstrained, nor as full as it might be; since one or two 
more good instances have occurred to our memory while looking 
over its columns. On comparing together the Australian and 
New Zealand columns, we find only fourteen blanks, not filled 
by known representative species ; a similar comparison of the 
New Zealand and South American columns shows forty-six 
blanks, sixteen of which are among the Endogens. 
On fairly weighing all this testimony, the botanist will perhaps 
accede to our author’s conclusion,—viz., that the floras of these 
three great areas of land in southern latitudes “exhibit a botan- 
ical relationship as strong as that which prevails throughout the 
lands within the Arctic northern temperate zones: and which is 
not to be accounted for by any theory of transport or of variation ; 
but which is agreeable to the hypothesis of all being members of 
a once more extensive flora, which has been broken up by ge- 
ological and climatic causes.” a. g. 
[Extracted from the American Journal of Science and Arts, 2nd Ser., Vol. XVII. !8S1.}