144 ESSENTIALS OF B ACTERIOuOG Y. 



Gelatine Plates. Yellowish-brown, irregular colonies, with 

 prolongations in every direction, forming all sorts of figures ; an 

 impression preparation shows these spider-leg processes to con- 

 sist of bacilli in regular order. 



Stab Culture. The gelatine soon liquid, a gray layer on the 

 surface, but the chief part of the culture in small crumbs at the 

 bottom. 



Pathogenesis. Rabbits and guinea-pigs injected subcutane- 

 ously die quickly, a form of toxaemia, hemorrhagic condition of 

 lungs and intestines present. When neurin is injected previ- 

 ously the animals do not die. This ptomaine is supposed to be 

 generated by the proteus vulgaris. 



Proteus Mirabilis. (Hauser.) 



Differs from P. vulgaris in that the gelatine is less rapidly 

 liquefied. Found also in putrid material. 



Proteus Zenkeri. (Hauser. ) 



Does not liquefy gelatine ; otherwise similar to the other two. 



We have now considered some of the characteristics of the 

 more important bacteria. The scope of this work does not allow 

 a more extended study than we have made, which, as we are 

 aware, has been very superficial. The larger works must be 

 referred to, if a deeper interest is taken in the subject. 



