No. 4.] Reprints. 23<> 



an easy matter to determine during the life of the horse whether any 

 particular disturbance of the digestive organs or lack of nutrition is 

 due to the presence of bots or to some other agency producing 

 similar symptoms, and even a competent veterinarian may be 

 puzzled, in diagnosis. If occasional bots are noticed in the excre- 

 ments of the animal together with poor condition, their presence in 

 numbers may be inferred. It must be remembered that the bots are 

 capable of withstanding almost any substance that the walls of the 

 stomach can endure, and the safest plan, if intending to dose for 

 them is to employ a veterinarian. Turpentine is perhaps most 

 generally given, but must be used with care. 



THE HiEMORRHOIDAL BOT-FLY. 



GastropJiilus JiwniorrJioidalis, Linn. 



While it is common to speak of the horse bot-fly, it should not 

 be inferred that there is but one kind parasitic upon the horse. 

 Take the world over, there are at least six well-defined species 

 occurring on the horse, ass, or mule, and any of these are liable to 

 be introduced into this country with imported animals. The above- 

 named species is probably next to egui, the most generally distri- 

 buted in this country. With the other allied species it was well 

 known in Europe during the last century and received mention or 

 more elaborate description from Linnaeus, DeGeer, Fabricius, and 

 other leading writers on entomology. 



Extent of injury.— -The losses to be referred to this species are 

 similar to those of the other species, but from the accounts of vari- 

 ous authors and what we have heard from persons who were plainly 

 describing the actions of this particular form, it is evident that the 

 excitement and consequent loss due to the attacks of the adult fly 

 are much worse with this species than the common one. This is 

 described by Clark as follows :— 



At the sight of this flv the horse appears much agitated, and moves his head 

 backward and forward in the air to balk its touch and prevent its darting on 

 the lips ; but the fly, waiting for a favourable opportunity, continues to repeat 

 the operation from time to time ; till at length, finding this mode of defence insuffi- 

 cient, the enraged animal endeavours to avoid it by galloping away to a distant 

 part of the field, if it still continues to follow and tease him, his last resource is in 

 the water where the CEstrus is never observed to follow hira. At other times this 

 CEstrus gets between the forelegs of the horse whilst he is grazing, and thus 

 makes its attack on the lower lip. The titillation occasions the horse to stamp 

 violently with his forefoot against the ground, and often strikes with his foot, as 



