710 



ORDER V. ACTINOMYCETALES 



orange, depending on the medium; cells 0.3 

 to 0.9 micron in diameter. 



After one j^ear of cultivation in peptone 

 broth, strains Nos. 43 and 45 dissociated to 

 form mycobacterial strains which were 

 closely related to each other. Cells were rod- 

 shaped, 0.8 by 0.5 to 2.5 microns, curving 

 and branching, changing to cocci in 3 to 5 

 days. Enlarged cells were formed on cer- 

 tain media. These showed no differences in 

 fermentative capacity as compared with the 

 original culture. Krassilnikov regards these 

 organisms as closely related to Mycobac- 

 terium brevicale on the basis of appearance of 

 cells, pigmentation of colonies and physio- 

 logical properties. Krassilnikov (loc. cit.) 

 recognizes as a subspecies Mycococcus tetra- 

 genus. 



Source: Isolated from soil at Yershovo 

 Station, Russia. 



Habitat: Infrequently found in soil. 



2a. Mycococcus ruber subsp. tetragenus 

 Krassilnikov, 1938. (Ray Fungi and Related 

 Organisms, Izd. Akad. Nauk, U.S.S.R., 

 Moskau, 1938, 121.) 



tet.ra'ge.nus. Gr. pref. tetra four; Gr. v. 

 gennaio to produce; M.L. adj. tetragenus 

 produced in fours. 



Original description supplemented by 

 material from Krassilnikov (Guide to the 

 Actinomycetes, Izd. Akad. Nauk, U.S.S.R., 

 Moskau, 1941, 126). 



Cells coccoid, occurring in tetrads formed 

 by the multiplication of two different 

 branches; occasionally combined into 

 parallel chains. Both types are consistently 

 found on synthetic agar. 



Colonies: Red; slightly enlarged; weak 

 shine. 



Physiological and cultural characteristics 

 are, in general, not different from those of 

 Mycococcus ruber. 



Comment: Krassilnikov regards this or- 

 ganism as a form of Mycococcus ruber. Two 

 strains have been isolated. 



Source: Isolated from soil. 



Habitat: Infrequently found in soil. 



3. Mycococcus capsulatus Krassilni- 

 kov, 1938. (Microbiologia (Russian), 7, Part 

 1, 1938, 349.) 



cap.su.la'tus. L. noun capsula a small 

 chest; M.L. adj. capsulatus encapsulated. 



Original description supplemented bj^ 

 material from Krassilnikov (Guide to the 

 Actinomycetes, Izd. Akad. Nauk, U.S.S.R., 

 Moskau, 1941, 127). 



Cells rounded, irregular in size, 0.7 to 1.0 

 micron in diameter, frequently occurring in 

 short chains of 3 to 7 cells. Cells surrounded 

 by a thick, slimy capsule. Chains sometimes 

 form side branches. Not acid-fast. Gram- 

 positive. 



Colonies : Rose or pale rose, slimy, spread- 

 ing. No soluble pigment. 



Physiological properties and fermentative 

 capacity are not different from those of 

 Mycococcus ruber. 



Comment : One of the two strains isolated, 

 No. 53, dissociated into strains with smooth 

 colonies and rod-shaped cells, 0.7 by 1.5 

 to 5.5 microns, without a slimy capsule. 

 Fermentative capacity no different from 

 that of the original culture. Krassilnikov 

 regards this strain as closely related to 

 Mycobacterium planum on the basis of its 

 cultural, morphological and physiological 

 properties. 



Krassilnikov (loc. cit.) regards this or- 

 ganism as a subspecies of Mycococcus muco- 

 sus. 



Source: Isolated from soil. 



Habitat: Infrequently found in soil. 



3a. Mycococcus capsulatus subsp. niucosus 

 Krassilnikov, 1938. (Ray Fungi and Related 

 Organisms, Izd. Akad. Nauk, U.S.S.R., 

 Moskau, 1938, 349.) 



mu.co'sus. L. adj. mucosas slimy, mu- 

 cous. 



Original description supplemented by 

 material from Krassilnikov (Guide to the 

 Actinomycetes, Izd. Akad. Nauk, U.S.S.R., 

 Moskau, 1941, 127). 



Cells occur in tetrads in one plane, occa- 

 sionally forming short, parallel chains and 

 joining chains, surrounded by a thin, slimy 

 capsule. There are also cells which form 

 individual cases of branching rods. Resting 

 cells are found. 



Cultural and physiological characters are 

 not different from those of Mycococcus cap- 

 sulatus. 



Comment: Krassilnikov regards this or- 



