BIO-CHEMICAL CHARACTERISTICS OF BACILLI. 93 



this reaction very definitely. Compared with a non-inocu- 

 lated tube of milk, or better with a tube clotted by the 

 action of b. coli, there is seen to be a distinct lessening of 

 opacity, but as mentioned before, no obvious peptonisation 

 as is seen in many of the proteus and other gelatin lique- 

 fiers. This reaction owing to the time taken to manifest 

 itself, cannot, however, be considered of much practical use. 



A few cultures did not show the reaction, but these are, 

 as one might expect, only found amongst those which pro- 

 duce the alkaline reaction slowly, probably if left longer 

 they too would show the change. 



This characteristic of the Gaertner group, which is a 

 very fundamental one, has been noticed by comparatively 

 few observers (19, 10). It is probably due to a slow pro- 

 teolytic action of the bacillus upon the "membranes" of 

 proteid between the fat globules which are liberated and 



rise to the top. 



Conclusions. 



1. The bio-chemical characteristics of forty "standard'' 

 (type Gaertner) cultures principally from European labora- 

 tories have been systematically tested, using a large 

 number of "sugars," milk, and litmus milk. 



2. There is a very close similarity in the bio-chemical 

 characteristics of the members of the group though fairly 

 wide individual variations in degree exist. 



3. On glucose, mannit, maltose, galactose and sorbit, 

 acid and gas are rapidly produced usually within forty-eight 

 hours, always before five days. 



4. On lactose, saccharose, dextrin, inulin, amygdalin, 

 raffinose, adonit and erythrit, no action is produced by any 

 of the strains incubated up to three weeks. 



5. On <lulcit, acid and gas is produced by all the strains, 

 but the time taken is usually longer than with the other 

 sugars, and is especially long in the hog cholera group. 



