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Does tbe same species of bacteria occur constantly in the same species 

 of legume year after year? 



The following descriptions are merely the beginning of an attempt to 

 investigate and answer these questons. 



For much of the culture work, I am indebted to Mr. T. R. Perry, one 

 of the students in Purdue University last year, 

 SPECIES 1. 



Separated twenty times from the nodules of Trifolium pratense. 



MORPHOLOGY. 

 Bacilli with rounded ends, occurring sometimes singly, but generally 

 in pairs. These bacilli measured from .75 to 1 mu in width, and 2 mu in 

 length. Examination of Zoogloea masses on agar shows a distinct capsule 

 formation sometimes measuring 3 mu in width and 4 mu in length. 



BIOLOGICAL CHARACTERS. 



An aerobic, liquefying, motile, chromogenic bacillus, growing well at 

 room temperature, but slightly better at 3714 C°. 



On gelatin plates the colonies are large and white, liquefying the 

 gelatin in a very short time. 



A funnel shaped liquefaction occurs in gelatin stab cultures in about 

 15 days, and a distinct greenish fluorescence is given to the liquid portion, 

 while a white precipitate sinks to the bottom of the "funnel." After all 

 the gelatin is liquefied, a distinct green mycoderm is formed on the 

 surface. 



On the agar streak there is a thin, spreading light-green growth which 

 imparts a distinct fluorescence to the agar. On older cultures, this growth 

 thickens and forms a luxuriant zoogloea mass all over the agar. It is 

 from such conditions that the capsule stage may be obtained. Upon 

 potato a slimy, yellowish, dirty-brown growth takes place along the line 

 of inoculation, which growth becomes darker with age. 



Milk is quickly coagulated, and the whey takes on a greenish fluor- 

 escence. This milk, however, remains neutral. 



In solutions containing nitrates, all nitrates are changed to nitrites in 

 from five to seven days. 



Glucose solutions are not fermented. 

 SPECIES 2. 



Separated several times from the nodules of Vicia sativa. 



