liOTs. 95 



place of existence for the offspring* of the gad-fly during about 

 ten months of its existence ; that it is attached to that part of 

 the inside coat of the stomach by its two hooks, and that its 

 mouth is quite buried in this ; and that its food is the mucous 

 secretion of the stomach. These facts should be borne in mind. 



JN^'ow, if the bots do commence boring, what is the cause of 

 it ? It can not be because the food in the stomach is distasteful 

 to them, for they never taste that ; their food is the secretion 

 of the stomach itself, not its contents. And, before any con- 

 siderable change can take place in the character of the mucus 

 secreted by the stomach, very serious disease of the stomach 

 itself, or of the horse's general system, must take place. 



When the bots commence boring, what is it for ? It is be- 

 cause their natural food has so changed that it is no more fit 

 for their use, and has actually become their poison. They then 

 set to work and bore to the second coat of the stomach ; but 

 their trouble is not yet relieved, and they may go on through 

 into the cavity of the abdomen or belly. But such change in 

 the character of the mucus can not take place until the horse 

 is far gone in disease, or nearly dead. In the great majority 

 of cases of disease, the bots remain perfectly quiet and secure 

 until the animal is dead. Their dwelling-place is then de- 

 stroyed, and their food becomes poison. They go to work to get 

 out, but get only into the cavity of the abdomen, their situa- 

 tion being not at all bettered by the change. 



From these reasons, it is certain that bots never attack a 

 healthy stomach, and hence, such a thing as a disease being 

 produced by their boring does not exist. They are in no case 

 the cause of any of those diseases which are so often pronounced 

 ''botsr 



If any one is not satisfied that the fact of bots being found 

 to have bored through the stomach is no evidence that they 

 produced the disease of which the horse died, let him open the 

 stomachs of any number of horses that have died in the spring 

 of the year, some hom-s after death, and, no matter what dis- 



