XI] BACILLI : SPECIFICALLY PATHOGENIC 243 



angular and filmy as those of bacillus coli. Compare Fig. 72, 

 which, although of the grouse bacilhis, is a good repre- 

 sentation of a bacillus coli plate, with Fig. 85, of a plate of 

 the typhoid bacillus. In gelatine streak and Agar streak 

 the growth is also markedly slower and more translucent 

 in the first few days than that of the bacillus coli, but its 



Flu. S9. — Streak Cultures on Nutrient Gel.^tin'e after 4" hours : on 



THE LEFT, OF BACILLUS COLI ; ON THE RIGHT, OF T^T'HOID BACILLUS. 



irregular filmy margin in the gelatine streak culture is the 

 same as in bacillus coli. 



5. In gelatine stab the line of inoculation is marked like 

 that of bacillus coli, as a row or rows of droplets white in 

 reflected, brownish in transmitted light, but on the surface 

 of the stab in typhoid the plate-like filmy expansion is 

 small, and is not well marked in the first few days, whereas 



