170 DADDS VETERINARY MEDICINE AND SURGERY. 



Persons who have paid any attention to the study of physiology, 

 are aware that these instinctive or involuntary movements, per- 

 formed without consciousness, are the birthright of a vast number 

 of the inferior orders of creation; therefore, it is not likely that 

 the bot would, even if he possessed the power, voluntarily vacate 

 a location favorable to its growth and development. 



Veterinary surgeons have long since discarded the absurd notion 

 that bots are the cause of any oain or suffering to horses. In fact, 

 some of the most distinguished of them assert that these little 

 creatures, with their rough exterior, are rather beneficial than 

 otherwise, and that, by friction and irritation, they arouse the 

 sluggishness of the stomach, and thus promote digestion. Per- 

 sons unacquainted with these facts are, therefore, apt to attribute 

 effects, during life, to causes which happen after death, and, conse- 

 quently, the poor horse has to be dosed with all sorts of nostrums. 



So popular has been the belief that bots are injurious to horses, 

 and, therefore, must be expelled at all hazards, that almost all the 

 old works on farriery contained some favorite recipe for their ex- 

 pulsion. Popular opinion, too, has been so much in favor of the 

 theory, that Mr. Perctvall thought it his duty, as a public 

 teacher, to make use of the following language : 



" You may boldly assert that bots are in nowise injurious. Still, 

 you can not persuade the world so, and, therefore, you must be 

 prepared to meet the complaints of those unbelievers, who will, 

 now and then, declare that their horses have bots, which must be 

 got rid of. But I know of no medicine that has the power of 

 destroying ; and even if we possessed such, I am not sure that we 

 could, even when dead, detach them from the cuticular coat of the 

 stomach, to which they are attached by small horns." 



In allusion to the parasites which infest the human body, "Wat- 

 son remafks: 



" It is a curious fact that numerous parasites do crawl over the 

 surface of our bodies, burrow beneath our skin, nestle in our en- 

 trail- and riot and propagate their kind in every corner of our 

 frame, producing ofttimes such molestation and disturbance as to 

 require the interference of medicine. Nearly a score of animals 

 that have their dwelling-place in the interior of the human body 

 have been already discovered and described, and scarcely a tissue 

 or an organ but is occasionally profaned by their inroads. Each, 

 also, has its special or its favorite domicile. One species enoosc* 



