532 



DESCRIPTION OF SPECIES. 



Potato is rapidly covered with a 

 purplish-red growth. Broth be- 

 comes turbid, and pink in colour. 



Milk is coagulated, and a blood- 

 red colour develops on the surface 

 and gradually extends. 



They were found in water. 



Bacillus rubescens (Jordan). 

 Rods 4 p in length, -9 p, in width, 

 singly, in pairs, and short chains. 



Colonies pure-white. 



Inoculated in the depth of gela- 

 tine there is a little growth in the 

 track of the needle, and a pure- 

 white prominent patch on the free 

 surface. 



On agar the growth is white and 

 shining, and later has a pink tinge. 



On potato the growth is flesh- 

 coloured. 



Broth becomes turbid, and a scum 

 forms on the surface. 



Milk after a time acquires a pink- 

 ish colour. 



They occur in sewage. 



Bacillus rubidus (Eisenberg). 

 Rods and filaments. 



Colonies circular, granular, and 

 slightly red. 



The bacilli inoculated in the depth 

 of gelatine produce liquefaction and 

 a brownish-red colour. 



On agar and potato they form a 

 brownish-red growth, and liquefy 

 blood serum. 



They occur in water. 



Bacillus sanguinis t y p h i 

 (Brannan and Cheeseman). Rods 

 1 to 2'5 p in length, -5 to '8 \L in 

 width ; singly, in pairs, and in 

 chains, and involution forms. 



Colonies granular, pale-brown. 



The bacilli inoculated in the 

 depth of glycerine-agar produce a 

 growth in the track of the needle 

 composed of isolated, minute, white 

 colonies. 



Ra'bbits inoculated die in from 

 two weeks to a month. 



They were isolated from the 

 blood of patients suffering from 

 typhus fever. 



Bacillus saprogenes (Rosen- 

 bach). Three rod-formed organ- 

 isms have been described by 

 Rosenbach as intimately associ- 

 ated with putrefactive processes. 



No. 1. Large rods (Fig. 210), 

 which form an irregular sinuous 

 streak with a mucilaginous appear- 

 ance when cultivated on nutrient 

 agar-agar. Spore-formation pre- 

 sent. They grow also very readily 

 on blood serum, and all cultivations 

 yield the odour of rotting kitchen 

 refuse. They are not pathogenic. 



No. 2. Rods shorter and thinner 

 than No. 1. They develop very 

 rapidly on agar-agar, forming trans- 

 parent drops, which become grey. 

 The cultivations yield a character- 

 istic odour similar to the last. 



FIG. 210. BACILLUS SAPROGENES, No. 1. 

 (Rosenbach. ) 



They are pathogenic in rabbits. 

 They appear to be identical with 

 Bacillus fcetidus (Bacterium fceti- 

 dum, Thin). They were isolated 

 from a patient suffering from pro- 

 fusely-sweating feet. 



No. 3. See Bacterium sapro- 

 genes. 



Bacillus scissus (Frankland). 

 Very short rods, 1 to 2 p in length, 

 and 1 p. in width. 



Colonies yellowish, opaque in the 

 centre, and periphery dentated. 



Inoculated in the depth of gela- 

 tine there is no growth in the 

 track of the needle, but a shining 

 layer forms on the surface, and the 

 jelly is coloured greenish. 



On agar the growth is shining 

 and the jelly coloured green. 



On potato the growth is flesh- 

 coloured. 



They occur in earth. 



Bacillus septicaemias haemor- 

 rhagicae (p. 231). 



Bacillus septicus (Klein). 

 Rods varying in size. Non-motile. 

 They form threads or leptothrix 

 filaments, and are rounded at the 

 ends. They are anaerobic, and form 

 spores independently of access to air. 



