376 



BACILLI WHICH CAUSE PUTREFACTION. 



greyish-white veil-like growth is formed, which is some- 

 what thicker, and irregular at the 

 margin. On potatoes the hacillus 

 forms luxuriant glistening, light- 

 brown cultivations ; on blood serum, 

 thick, whitish lines. In all these 

 nutrient media a foul smell is de- 

 veloped. Animals are not affected 

 by small doses administered subcu- 

 taneously, but when the quantity is 



larger a localised suppuration occurs. 



Fig. 100. Bacillus 

 P fpasset) xV90 US 



Bienstock's 



faeces. 



Bacillus putrificus coli (Bienstock). 



These are thin, actively moving rods, about 3 /*. in 

 length, though often shorter, and often arranged in the 

 f orm O f i on g threads. When spore formation takes 

 place a thickening of the rod occurs at one, or, more 

 rarely, at both ends, and this thickened part becomes 

 gradually isolated from the rod, and assumes a spherical 

 Spore forma- form. This spore remains for some time in connection 

 germination. with the rod, giving it thus the form of a drum-stick, 

 and the rod continues to move about with the spore 

 attached to it, that end of the bacillus being in front. 

 As the result of the gradual disappearance of the rod 

 the spherical and very highly refracting spore becomes 

 free ; if this spore is introduced into suitable nutrient 

 material it becomes narrower and gradually elongates 

 to form a rod. From these freshly formed rods 

 chains of very short rods arise, these shorter bodies 

 gradually growing to form longer rods and threads. 

 The growth of the bacilli on nutrient gelatine has 

 at first a mother-of-pearl aspect, but as it becomes 

 older it acquires a yellowish colour, and presents a 

 homogeneous appearance without any striped arrange- 

 ment. More accurate statements as to the cha- 

 racters of growth are as yet wanting. Bienstock was 

 able to demonstrate by careful analytical fermentative 

 experiments that the bacilli can split up albumen ener- 

 getically ; when small quantities of a cultivation of 



