New YorK AGRICULTURAL EXPERIMENT STATION. 113 
EXAMINATION OF CULTURES IN 19006. 
Duplicate acre packages for three legumes were purchased from 
each of three seedsmen, or eighteen packages in all. Mr. C. K. 
Scoon, a local farmer, very kindly made the purchase for us. 
The cultures had all been put up by the National Nitro-culture 
Co., and since they bore the date 1906 were surely not old cultures 
which had been long in the hands of the seedsmen. Twelve pack- 
ages, six for alfalfa and six for crimson clover, were contained in 
the metal tubes, while the six cultures for vetch were wrapped in 
parchment paper and tin foil, as was the case with the packages 
last season, This could hardly have been an accident since it was 
equally true of the cultures received from each of the three seeds- 
men. 
Method of making the examinations.——The chemicals used in all 
cases were those accompanying the cultures. They were dissolved 
in the appropriate amount of rain water and the solutions sterilized 
in order to reduce the chance of outside contaminations and enable 
us to determine just what germs were on the cotton. In making a 
test of these commercial cultures the packages were carefully opened 
and the inoculated cotton divided into three equal portions with 
sterile instruments and under conditions which exposed the material 
to the least possible opportunity for contamination. In each case 
one of these portions was-placed in.a flask containing 100 c. c. of 
the sterile nutrient solution above described. The remainder of the 
cotton was returned to the original container and sealed as before. 
The flasks were held at 25° C. (77° F.). At the end of twenty- 
four hours the proper amount of sterile ammonium phosphate was 
added. The formation of turbidity was noted and the contents ex- 
amined by means of hanging drop and stained cover glass prepara- 
tions. Peptone-free agar plates were inoculated from each flask 
at the end of two, and again at the end of five days. Any colonies 
resembling the legume bacteria which appeared upon the plates were 
given further study. 
In the case of each examination of these cultures two series of 
control flasks were also used. One series received the same treat- 
ment as the test flask with the exception that in place of the cotton 
these flasks received a portion of a pure culture of legume bacteria. 
In the other series the flasks received the same chemicals and ex- 
posure to contamination but did not receive either cotton or in- 
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