290 DISEASES OF THE STOMACH. 



these larvae The little horse I had hired for the occasion 

 became so lazy and unwilling to go on, and moved so 

 awkwardly, that I could not keep pace with my company, 

 and I was at a loss how to proceed ; when, on casually 

 taking up the tail, I discovered three or four of these insects 

 hanging to the rectum, and their removal instantly proved a 

 cure/^ Its change to the chrysalis state, and further trans- 

 formation into that of insect, which happens in about two 

 months, is similar to what befals the oestrus equi. 



Of the (estrus veterinus, or red bot — so designated 

 by Mr. Clark in preference to retaining the epithet nasaliSj 

 which conveys a false notion of its habitation — the same 

 historical detail does not appear to be made out ; for our 

 author commences his account of it by saying, " The mode 

 of this insect depositing its eggs or nits is at present un- 

 known. By watching for them on the commons in the Avarm 

 days of the sixth and seventh months (July and August) it 

 might be detected, I apprehend, without very great difficulty. 

 They, perhaps, deposit them about the lips or legs, as the 

 former species. The larva of this species is also not cer- 

 tainly known. That it inhabits the stomach, as the two 

 former species, there is little doubt ; and I have taken con- 

 siderable pains to search for it at the slaughter-houses, and 

 have found a species in the stomach which widely differs 

 from the equi and hemorrhoidalis , and which I presume may 

 be the larva of this : though it is possible there may be a 

 fourth species inhabiting the stomach of the horse, in which 

 case it may be still doubtful, so that I do not positively 

 assert it to be this larva belonging to the veterimis. 



'' This larva, if it is the veterinus, mny be known from 

 the two preceding species, being smaller^ of a more tapering or 

 oblong figure, and the segments more detached and rounded, 

 shining, smooth, and of a pellucid red or ruby colour, more 

 particularly at the tail or obtuse end.'' 



After having described a fourth species, or what he 

 apprehends to be so, from some peculiar characters it 

 possesses, Mr. Clark asserts that he once found the real 

 chrysalis of the veterinus in the neighbourhood of Worcester, 



