272 MANUAL OF BACTERIOLOGY. 



germicides. It grows best at about 30 C. upon the ordinary 

 culture- media; milk is peptonized. Bacillus subtilis may 

 easily be isolated in pure culture by adding finely cut hay to 

 tubes of bouillon; placing these in the steam sterilizer for five 

 or ten minutes; then letting the tubes develop in the incubator. 

 Plates made from the bouillon will probably show colonies of 

 the Bacillus only, as the steam may be expected to have de- 

 stroyed all organisms except its very resistant spores. 



FIG. 59. Bacillus subtilis. (X 1000.) 



The hay bacillus has certain congruers, and it is perhaps 

 more correct to speak, as is often done, of the "hay bacillus 

 group" rather than of a special organism. Some of the con- 

 gruers have been found in pure culture in cases of panophthal- 

 mitis following injury. Moreover, injections of cultures of 

 the organism so obtained, produced panophthalmitis in experi- 

 ment animals.* 



*Silberschmidt Ann. de F Institute Pasteur. 1903. p. 268. Also see 

 Kneass and Sailer. Univer. Pennsylvania Med. Bull. June, 1903. 



