FAMILY II. RHIZOBIACEAE 



295 



Potato: Yellow to deep violet, rugose, 

 spreading growth. 



Indole not produced. 



Usually no acid from glucose, maltose or 

 sucrose. No acid from lactose. 



Nitrites produced from nitrates. 



Aerobic, facultative. 



Temperature relations: Optimum, 30° C. 

 Good growth in 7 days between 2° and 4° C. 

 No growth at 37° C. 



Comment: The most characteristic fea- 

 ture of the original culture of this species 

 was its ability to grow a heavy, folded, mem- 

 branous pellicle on gelatin stabs and other 

 media. The original culture also sometimes 

 produced a metallic sheen. If the descrip- 

 tions of all of the cultures regarded by 

 Cruess-Callaghan and Gorman (Scientific 

 Proc. Royal Dublin Soc, 21, 1935, 219) as 

 C. amethystinum are taken into account, 

 there really are no other important charac- 

 ters by which this species can be separated 

 from C. violaceum. Moreover, those that 

 have studied many cultures of these violet 

 organisms over a long period of time, with 

 replatings to purify, report that this mem- 

 branous growth may develop on almost 

 any subculture of typical C. violaceum. The 

 formation of this heavy, folded growth 

 should therefore probably be regarded as a 

 dissociation phenomenon. Further com- 

 parative studies will presumably show that 

 C. amethystinum should be regarded as a 

 variant form of C. violaceum. 



Source: Isolated once by Jolles from 

 spring water from Spalato. 



Habitat: Water. 



3. Chroniobacterium janthinuni 



(Zopf , 1883) Holland, 1920. {Bacterium jan- 

 thinum Zopf, Die Spaltpilze, 1 Aufl., 1883, 

 68; Holland, Jour. Bact., 5, 1920, 222.) 



jan'thi.num. Gr. adj. janthinus violet- 

 colored. 



Rods, 0.5 to 0.8 by 1.5 to 5.0 microns, 

 occurring singly. Motile with peritrichous 

 flagella. Gram-negative. 



Gelatin colonies: Circular, yellow, be- 

 coming violet. 



Gelatin stab: White to violet surface 

 growth. Infundibuliform liquefaction. 



Agar colonies: Creamy center, violet 

 margin. 



Agar slant: Yellowish, moist, gummy, 

 glistening growth becoming deep violet. 



Broth: Turbid, with light violet pellicle. 



Litmus milk: Violet cream layer. Litmus 

 decolorized from below. Rapid digestion. 



Potato: Violet to violet-black, spreading 

 growth. 



Indole not produced. 



Acid from glucose. No acid from maltose, 

 lactose or sucrose. 



Nitrites generally produced from nitrates. 



Aerobic, facultative. 



Temperature relations: Optimum, 30° C. 

 No growth between 2° and 4° C. Grows well 

 at 37° C. 



Source: Isolated from pieces of pig's blad- 

 der floating on badly contaminated water. 



Habitat: Water and soil. This appears 

 to be the species that causes a fatal septi- 

 cemia in animals and man. 



4. Chromobacterium niarismortui 



Elazari-Volcani, 1940. (Studies on the Mi- 

 croflora of the Dead Sea. Thesis, Hebrew 

 Univ., Jerusalem, 1940, VII and 76.) 



ma.ris.mor'tu.i. L. noun mare the sea; 

 L. gen . noun maris of the sea; L. adj . mortuus 

 dead; M.L. gen. noun marismortui of the 

 Dead Sea. 



Rods, the length of which varies greatly 

 with the concentration of salt and media. 

 On agar media, in 3 to 24 per cent salt, the 

 cells are usually 0.5 by 1.3 to 3.0 microns; 

 in liquid media, 4.5 to 13.0 microns. Occur 

 singly and in pairs. In 0.5 and 30 per cent 

 salt and in Dead Sea water, the cells are 

 usually very long, twisted threads. Motile 

 by means of 4 to 6 peritrichous flagella. 

 Gram-negative. 



Gelatin stab (12 per cent salt-1 per cent 

 proteose peptone-15 per cent gelatin) : Fili- 

 form, blue-brown, nailhead surface growth. 

 Very slight infundibuliform liquefaction 

 after six weeks. 



Agar colonies (12 per cent salt-1 per cent 

 proteose peptone-2 per cent KNO3) : Circu- 

 lar, smooth, entire, slightly convex and 

 concentrically ringed with dark brown cen- 

 ters followed by blue-brown, gray-brown 

 and yellow rings and a colorless transparent 

 margin. On removing the colony, a print 

 remains in the agar consisting of three 

 zones : a blue center, a brownish gray inner 



