170 ESSENTIALS OF BACTERIOLOGY. 



so as to form a circle or pear-shaped growth, from which linear 

 grooves again start. 



Stab Culture. Grows first on surface, then gradually along 

 the needle-track, long processes shooting out from the same, 

 clouding the gelatine. Later, air-bubbles form like the cholera 

 culture, and in two weeks the whole gelatine liquefied. 



Staining. Do not take aniline dyes very well. Gram's method 

 is, however, applicable. 



Pathogenesis. If a pure culture is spread over the honey- 

 comb containing bee larvae, or if bees are fed upon infected 

 material, foul-brood disease will occur. Mice, if injected, die in a 

 few hours. (Edema around the point of infection, and many 

 bacilli contained in the cedematous fluid, otherwise no changes. 



Micrococcus Amylovorus (Burrill.) 



Origin. In the disease called " Blight," which affects pear- 

 trees and other plants. 



Form. Small oval cells, never in chains, more the form of a 

 bacillus. 



Pathogenesis. Introduced into small incisions in the bark of 

 pear-trees the trees perished from the " blight." The starch of 

 the plant cell was converted into carbon dioxide, hydrogen, 

 and butyric acid. 



Bacterium Termo. (Cohn.) 



This was a name given to a form of micro-organism found in 

 decomposing albuminous material, and was supposed to be one 

 specific germ. Hauser, in 1885, found three different distinct 

 microbes which he grouped under the common name of Proteus, 

 which have the putrefying properties ascribed to B. Termo. 



Proteus Vulgaris. 



Origin, In putrid animal matter, in the feces, and in water. 



Form. Small rods, slightly curved, of varying lengths, often 

 in twisted chains, having long cilia or flagella. 



Properties. Very motile, and very soon liquefying gelatine ; 

 forms hydrogen sulphide gas ; causes putrefaction in meat. 



Growth. Growth very rapid, best at 24 C., is facultative 

 aerobic. 



Gelatine Plates. Yellowish-brown, irregular colonies, with 

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



