159 



MORPHOLOGY. 



In crushed nodules the "bacteroid" appearance is quite common, while 

 on the various artificial culture media these are rarely seen. Upon these 

 media, they appear as bacilli with rounded ends, often united in pairs. 

 They measure .8 mu in width and 1.5 mu in length. 



BIOLOGICAL CHAK ACTEES. 



This form is a faculative anaerobe, motile, .non-liquefying, non-chrom- 

 ogenic. Grows well at the room temperature, and better at the body 

 temperature. In gelatin stab cultures a line of very small colonies is 

 formed along the line of puncture. 



On agar plates the colonies appear in thirty-six hours, the surface 

 colonies having a whitish appearance, while the deeper ones have a yel- 

 lowish tinge. 



The agar streak gives rise to a slimy, viscous, whitish growth, having 

 no tendency to spread over the agar. 



On potato, a rather restricted whitish growth takes place very slowly, 

 and this growth is very slimy. 



In solutions containing nitrates, after twenty days, a considerable por- 

 tion have been reduced to nitrites, but not all, as there was positive test 

 for nitrates as well as for nitrites. 



Glucose solutions are not fermented. 



Milk is not coagulated, yet is rendered strongly acid. 

 SPECIES 3. 



Separated in several instances from nodules of Phaseolus nasus. 



MORPHOLOGY. 



Bacilli with rounded ends, usually united in pairs. 

 Measurement, 1.5 mu in width, 3 mu in length. 



BIOLOGICAL CHARACTERS. 



An aerobic, liquefying, motile nonchromogenic bacillus, which grows 

 very slowly at the room temperature, but quickly at the body tempera- 

 ture. In gelatin stab cultures the liquefaction occurs in a straight line 

 across the tube. The whole mass of gelatin becoming liquefied in 15 days. 



On gelatin plates the colonies reach one-sixteenth of an inch in diam- 

 eter, circular in outline. 



