CARNEGIE INSTITUTION OF WASHINGTON
DEPARTMENT OF GENETICS

COLD SPRING HARBOR, LONG ISLAND, N. Y.

November 1h, 1956

Dr. J. Lederberg
Department of Genetics
University of Wisconsin
Madison, Wisconsin

Dear Joshua,

I am sending you some phages,
including T2L (for Luria) and TD (for
Doermann), along with our E. coli S, a
smooth strain sensitive to all the phages.
It has no particular advantage over B
except that it makes nice white plates.

Our BE. coli H, which I am not
sending, is useful only with my variety
of T2 (T2H) and is resistant to Th.

Congratulations for the unifica-
tion of protoplasts and L forms.

Sincerely,

Ce.

A. D. Hershey
ADH: kk