SPECIES DESCRIBED BY VARIOUS WRITERS. 21.5 



liquid. If cultivated in a capsule containing 5 per 

 cent, of nutrient gelatine, a few hours after inocula- 

 tion the most characteristic movements of the in- 

 dividual bacilli are observed on the surface of the 

 nutrient gelatine, although at this early stage no 

 superficial liquefaction can be detected. Others 

 have stated that the movements occur in a thin 

 liquid film. The movements are not observed if 

 the nutrient medium contains 10 per cent, of gela- 

 tine. 



Proteus mirabilis.* Cocci -4 p -9 p. They 

 occur singly and in zooglcea, and sometimes in 

 tetrads, pairs, chains, or as short rods in twos 

 resembling Bacterium termo, in fact, in all con- 

 ceivable transition-forms. Cultivated on nutrient 

 gelatine they form a thick, whitish layer in con- 

 centric circles, which in time liquefies the medium. 

 Similar movements are observed in capsule- cultiva- 

 tions as with Proteus vulgaris. 



Proteus Zenkeri. Cocci, -4 p, and short 

 rods in twos like Bacterium termo; 1*65. //, long. 

 Cultivated on nutrient gelatine no liquefaction 

 results, but a thick, whitish -grey layer is formed. 

 The bacilli are motile, and the same phenomena 

 are observed on the solid medium, as in the other 

 forms. In cover-glass impressions most varied 

 groupings of the bacilli are seen, and also develop- 

 mental and involution-forms. 



Actinomyces. Actinomycosis is a disease 



* Hauser, ibid. 



