290- Manual of Veterinary Microbiology. 



being destroyed, in such case, by the phagocytes ; it 

 excites an active diapedesis which may be observed 

 after injections into the anterior chamber of the eye. 

 The toxines of cultures, on the other hand, seem to 

 repel the leucocytes and thus protect the microbes 

 from their destructive action. Certain other sub- 

 stances may take the place of this action : inoculation 

 of spores alone is followed by tetanus when lactic 

 acid, diluted to 1 to 500, or trimethylamin, is injected 

 at the same time, or when a contusion is produced in 

 the inoculated tissues. Simultaneous injection of the 

 germs of tetanus and the micro-bacillus prodigiosus 

 also allows the irruption of the disease; the prodigio- 

 sus attracts the phagocytes to itself and thus forms a 

 barrier behind which the tetanus bacillus multi[)lies 

 and secretes its protective toxines. 



The experiments of Yaillard and Yincent have been 

 repeated by Sanchez-Toledo, who seems to have suc- 

 ceeded in transmitting the disease by means of cult- 

 ures freed from their toxines and from all adjuvant 

 substances. 



Etiology and pathogeny. — The tetanus bacilli or their 

 spores exist in the soil ; the disease has often been 

 produced by inoculation of water with which certain 

 specimens of soil have been washed. From the soil 

 they are transported in the dried forage, pass un- 

 changed through the. digestive canal of herbivora and 

 with the manure are returned to the soil. By inocu- 

 lations they have been demonstrated in hay and in 

 the excrements of healthy horses and cattle. Tetanus 

 is therefoi^e of telluric origin; but it can also be trans- 

 mitted from one animal to another, either directly or 

 indirectly. The microbe being inactive when inhaled 



