120 NOTES ON VIBRIO DENITRIFICANS, SEWERIN, 



The main points of difference are that Bad. Hartlehii grows well 

 in nitrate and ordinary bouillon at 37°, gas production is more 

 vigorous at 22°, and it is a short rod without the vagaries of form 

 which occur in Vibrio denitrificans. 



The swollen organisms as depicted by Sewerin are similar to 

 those found in cultures of Rhizohium legiwiinosarum. As I have 

 shown in my paper on the latter organism, the appearance is due 

 to a swollen gelatinous capsule which gathers round the junctions 

 of the organisms. 



It is unfortunate that Sewerin named the organism Vibrio. 

 He apparently mistook the bent double cells for simple cells, and 

 was influenced by Zettnow, who published drawings of Vibrio 

 rugula, some of which are similar to the y- and y-forms of 

 Sewerin's organism. I have alread}'^ pointed out that Rhizobium 

 leguminosarum is a budding fungus, and there is every reason to 

 believe that Vibrio deiiitrificans is precisely* of the same order. 

 As it simulates a bacterium, the name Mycobacterinm denitrificans 

 would be more appropriate, while the species name is still main- 

 tained. Mycobacterium, as a name for those organisms which in 

 cultures may assume a more or less mycelial character, has been 

 suggested by Lehmann and Neumann.* In this group of 

 organisms are included the plague, glanders, diphtheria^ tubercu- 

 losis, and nodule organisms, all of which have ))een shown to 

 produce, under certain circumstances, branching or m3^celial 

 forms. t According to Migula's classification, the order Myco- 

 bacteriaceoi develops Y-shaped forms with true branchings. Neither 

 Rhizobium leguminosarum nor Vibrio (Mycobacterium.) denitri- 

 ficans forms true branching of the organisms, unless we agree to 

 call everything within a single capsule an organism, and this 



* Lehmann and Neumann, Diagnostik. Chester, Studies in Systematic 

 Bacteriology; Eleventh Annual Report Delaware College Agricultural Experi- 

 mental Station, 1898-99. 



t Skschivan, (Plague) Centralblatt fiir Bakt., i. Abt., xxviii., 289. Marx, 

 (Glanders) ibid, xxv., 274. Schulze, (Tuberculosis) Zeitsch. fiir Hygiene 

 xxxi., 153. 



