84 ESSENTIALS OF BACTERIOLOGY. 



all on the surface, a few separated colonies following the needle 

 thrust for a short distance. Agar, a very beautiful yellow, 

 along the stroked surface. 



Sarcina Aurantica. Flava, rosea, and alba are some of the 

 other varieties. Many are obtained from beer. 



Sarcina Ventriculi. (Goodsir.) 



Orifjin. Stomach of man and animals. 



Form. Colorless, oval cocci, in groups of eight and packets 

 of eight. 



Properties. Does not liquefy gelatine ; shows the reaction of 

 cellulose to iodine. 



Growth. Rapid. At end of thirty-six hours, round, yellow 

 colonies, from which colorless cocci and cubes are obtained. 



Habitat. They are found in many diseases of the stomach, 

 especially when dilatation exists. 



CHAPTER II. 



PATHOGENIC BACTERIA. 



WE have divided this part into two portions.* 



I. Those bacteria which are pathogenic for man and other 

 animals. 



II. Those bacteria which do not affect man. but are patho- 

 genic for the lower animals. 



Here again it will only be possible to give the more impor- 

 tant bacteria ; there are many diseases in which micro-organisms 

 have been found, but the}' have not yet been proven as causa- 

 tive of the disease, and have also been found in other diseases. 

 We cannot treat of them here. 



Bacillus Anthracis. (Bayer and Davaine.) Bayer and Da- 

 vaine, in 1850, first described this bacillus ; but Pasteur, and 

 later -Kbc/t, first gave it the importance it now has. 



Synonyms. Bacteridie du charbon (Fr. ), Milzbrand bacillus 

 (germ) ; bacillus of splenic fever, or malignant pustule. 



Ori'jin. In blood of anthrax-suffering animals. 



