668 THE NODULE ORGANISM OP THE LEGUMINOS^, 



as a straight or bent rod, the protoplasm of which has collected 

 in four places. 



A hanging-drop preparation of a two days old culture in 

 peptone-glucose fluid at 22° C. shows the young cell as actively 

 motile, darting about over the field of the microscope. At a later 

 stage it has a forward waltzing motion, and ultimately the motion 

 ceases when the cell presumably begins to bud. When the bud 

 has separated from the parent protoplasm it pulls and tugs in its 

 endeavour to free itself from the capsule membrane containing 

 the motionless mother cell, and we have an appearance exactly 

 like that of an ant attempting to drag along a twig which proves 

 too heavy for its powers. 



The capsule is frequently too strong, and the bud grows to 

 maturity still enclosed in the parent membrane. In young 

 cultures budding is very vigorous, and a second Ijud may appear 

 pushing the first to one side. Thus there is produced the Y form. 

 Another bud may form an X. 



In peptone sucrose media the irregular forms are very common; 

 indeed with a two days' culture there are very few individual 

 cells. These combinations clearly result from the inability of the 

 daughter cells to escape from the parent membrane, which is 

 apparently much more tough than when glucose is used as a 

 nutrient. When grown upon solid media, the cells are generally 

 in the rod form, but this does not justify their being placed 

 among the bacteria. Indeed, since they are budding fungi, the 

 name applied to them by Beijerinck is a misnomer. 



A year ago Maria Dawson, by constant observation under high 

 magnification, found that the organisms divided into equal or 

 slightly unequal halves, but since they divided, this investigator 

 considered that they were true bacteria. As before mentioned, 

 the organisms are too small to be seen clearly in the unstained 

 condition, and the observation of even the more mature buds is 

 a matter of some difficulty. The younger buds enclosed in the 

 ref ractile membrane are probably impossible to be seen until they 

 have attained a more mature form, when they appear as if 

 division had occurred. 



