508 



DESCRIPTION OF SPECIES. 



lactic acid bacillus is growing be- 

 comes sky-blue from the first. 



They are non-pathogenic. 



They are present in blue milk. 



Bacillus cyanogenus (Jordan). 

 — Rods 1'3 fi in length, "8 ft in 

 width. Slightly motile. 



Colonies granular and irregular. 

 They colour the surrounding gela- 

 tine brown. 



Inoculated in the depth of gela- 

 tine the bacilli produce a scanty 

 growth in the track of the needle, 

 and a film on the surface with 

 coloration of the gelatine beneath 

 it. 



On agar they form a white layer, 

 and the jelly is coloured brown. 



On potato the growth is brown. 



They were isolated from sewage. 



Bacillus cystiformis (Clado).— 

 Short slender rods. Motile. 



Colonies circular, yellowish, gra- 

 nular. 



Inoculated in the depth of gela- 

 tine there is a scanty growth in the 

 track of the needle, and a white 

 patch on the free surface. 



On agar the growth is yellowish- 

 white. 



They were isolated from urine. 



Bacillus delioatulus (Jordan). 

 — Rods 2 jj, long and 1 /j, broad, 

 often in pairs or short chains. 

 Actively motile. Spore-formation 

 not observed. 



Colonies at first whitish with 

 a radiating edge. Later they 

 liquefy the gelatine and the centres 

 become dark. 



Inoculated in the depth of gela- 

 tine they rapidly liquefy it and 

 form a whitish pellicle and a brown 

 deposit. 



On agar a greyish crinkled 

 growth appears, which gradually 

 becomes white and shining. 



On potato there is a grey flat 

 growth. 



Milk is coagulated and becomes 

 strongly acid. 



Broth is made turbid and a white 

 serum and precipitate formed. 



They occur in sewage. 



Bacillus dentalis virldans 

 (Miller). — Rods slightly bent, singly 

 and in pairs. 



Colonies circular, yellowish and 

 concentric. 



Inoculated in the depth of gela- 

 tine they grow in the track of the 

 needle and on the free surface, and 

 the jelly is coloured green: 



On agar the growth is colourless, 

 or slightly grey. 



Intraperitoneal injections in mice 

 and guinea-pigs produce a fatal re- 

 sult. Subcutaneous injectidns cause 

 suppuration. 



They were isolated from caries 

 of the teeth. 



Bacillus dentriticus (Bordoni 

 Uflrreduzzi and Lustig). — Rods Sb- 

 to 2-8 fi long, and '5 to -86 /i broad, 

 singly and in zoogloea. Motile. 

 Spore-formation not observed. 



Colonies have an arborescent 

 appearance. 



Inoculated in the depth of gela- 

 tine they form a circular raised 

 growth at the point of puncture, 

 and white colonies along the needle 

 track. The jelly is gradually 

 liquefied. 



On agar and blood serum there 

 is a scanty growth on the surface 

 and an abundant growth in the 

 track of the needle. Blood serum 

 is liquefied after some time. 



Broth is rendered turbid ; a 

 white firm pellicle forms. 



On potato there is a thick moist 

 white growth, which later becomes 

 yellow. 



Pound in water. 



Bacillus devorans (Zimmer- 

 manu). — Bods -99 /m to 1-2 /i in 

 length, -74 ^ in width ; singly, in 

 pairs and in chains. 



Colonies are circular, granular, 

 and grey, with periphery formed of 

 radiating processes. 



In the depth of gelatine they 

 produce a whitish filament and an 

 excavation at the upper part, which 

 may or may not contain liquefied 



jelly. 



On agar a greyish film is found. 



They do not grow on potato. 



They occur in water. 



Bacillus diffusus (Prankland). 

 — Bods 1'7 /i in length, '5 /i in 

 width ; singly, in pairs, and fila- 

 ments. 



