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New YorRK AGRICULTURAL EXPERIMENT STATION. 59 
these days in the examination of the Department cotton. The 
plates inoculated from the nodules and from the cotton solutions 
were grown side by side. While the plates representing the 
cotton solutions failed, all but one of the plates inoculated from 
the nodules developed colonies which closely resembled the 
description of Ps. radicicola. Transfers from these colonies were 
later compared with the authentic cultures from Washington 
and are thought to be identical. In many of the plates from the 
nodules the growth of Ps. radicicola was both abundant and prac- 
tically pure. | 
Exception may be taken that inoculating from the nodule 
introduced a trace of nitrogen into the cultures. The repeated 
transfers from the first tube to a second and from this to a third 
must have reduced this trace of nitrogen very considerably. 
However, in order to insure purity in the stock culture, transfers 
from these colonies were again plated on a portion of the same 
media and grew equally well. In this case the parallelism with 
the media used for the cotton was above reproach. 
From all this it would seem: fair to assume that the media were 
favorable for a development of Ps. radicicola had it been present 
in any considerable quantities upon the cotton. Isolation of 
Ps. radicocola from different legumes was carried out on this 
and similar media at various dates but these two cases are cited 
since the media and conditions were identical with those em- 
ployed in the working with the cotton.’ 
PURCHASE OF COMMERCIAL CULTURES. 
The purchase of commercial cultures for alfalfa, cowpea, and 
soy beans was made through Mr. J. B. Anderson. Packages of 
each were obtained from Jas. Vick’s Sons, Rochester, N. Y., 
J. M. Thorburn & Co. and Peter Henderson & Co., New York, 
and J. A. Salzer, LaCrosse, Wis. These widely separated firms 
were expected to furnish a fair sample of the market supply. 
All of the packages bore the stamp and contained the advertis- 
ing matter of the National Nitro-Culture Co. 
7Four other packages from the Department laboratory were examined with 
entirely similar results. We do not assume, however, by stating this fact 
that the Department cultures have generally been worthless. That question 
we have not compassed in a comprehensive way. Our main purpose has 
been to ascertain the value of the cultures put out by commercial houses, 
