308 J. S. LAWRENCE AND W. W. FORD 



washed-out forms. It shows however a distinct tendency to 

 produce curved or spiral forms. On the basis of this one char- 

 acteristic it is hardly justifiable to make it a distinct species. 

 It should be noted that this use of the term "graveolens" is 

 probably incorrect since a Bacterium graveolens was described 

 by Bordoni Uffreduzzi (1886) in 1886. This was a small non- 

 sporulating bacillus producing a green pigment. (Figures 43 and 

 44.) 



v Bacillus cohaerens Gottheil 1901. 



This organism was described by Gottheil (1901) in 1901 but 

 according to Chester it is identical with Bacillus simplex. The 

 culture of Bacillus cohaerens received from the Krai collection 

 is distinct from Bacillus simplex and is represented by four 

 organisms isolated in Baltimore, one from milk and three from 

 soil. The present description applies to all five strains. 



Morphology. Small, rather uniform homogeneous organisms 

 with rounded ends, measuring 0.375 to 0.5625 by 0.75 to 2.25 mi- 

 crons in 24 hour cultures on plain agar. On glucose agar the bacilli 

 are thicker and longer measuring 0.5625 to 0.75 by 2 to 5 microns. 

 On both media shadow forms appear early often in 24 hours. 

 These are made up of faintly-staining protoplasm with deeply- 

 staining particles in various positions, at the ends, towards the 

 center, or at the periphery. (Figures 15, 16, and 17.) 



Motility. Actively motile in 24 hour cultures. 



Staining properties. Gram-positive. 



Spore formation. Spores were formed slowly and sparsely 

 in the Krai culture and in one of ours. They appeared in about 

 10 days, were oval or elliptical, arose in the centers of the rods 

 which were slightly bulged on sporulation. The free spores 

 were very delicate and stained with difficulty. They measured 

 about 0.5625 by 0.75 microns. In a more recent isolation of 

 our own the spores appeared in 48 hours, were central or excen- 

 tric, bulged the rods and later retained distinct rims of protoplasm, 

 measuring 0.75 by 1.5 to 1.5 microns. Later the spores lost 

 their protoplasm, became more oval and measured 0.5 to 0.5625 

 by 0.9375 to 1.25 microns. Rarely the spores retained unequal 



