BOTS. 291 



under some horse duug — a drawing of which he gives from 

 memory. 



Summary. — The ovum, nit, or egg of the bot, then, it 

 appears, being deposited, some time in the autumn, upon the 

 hair, becomes licked by the tongue, by the heat and moisture 

 of which it is instantly hatched, and its larva liberated 

 and absorbed. Along with the food, the larva is conveyed 

 into the stomach, where it fixes its residence for the winter, 

 insinuating its tentacula into the cuticular coat. In the 

 spring of the year it withdraws its hooks, descends from the 

 stomach into the intestines, and is carried along with the 

 alimentary mass to be expelled with the faeces. Its expo- 

 sure in the dung is quickly followed by its desiccation and 

 contraction into the state of chrysalis j out of which, in about 

 two months, it undergoes its last metamorphosis into the 

 insect called a gad-fly. 



Professor Guiseppe Lossona, in contradiction of the 

 foregoing account, is of opinion that all the alleged kinds 

 of bots described by different authors, resolve them- 

 selves into a single species. His words are — "As to the 

 number of species of those insects whose larvce inhabit the 

 stomach of monodactyles, contrary to the accounts of Bracy 

 Clark, Meigdeu, Macquarr, and others, in my opinion, there 

 is but one. Although there exist slight differences in the 

 colour of the down of the face, in the hair upon the chest, and 

 in the rings round the abdomen of the animal, such varia- 

 tions are but accidental, dependent on the locality in which 

 they happen to be found : having myself proved that such 

 insects as come out of larvae that have been lodged in rotten 

 oak trees are of a darker colour ; while such as come out of 

 the dust of the poplar tree, or out of sand, are lighter 

 coloured, and clearer. ^^ ^ 



We now come to the 

 - Probable Efeects of Bots on Animals : a subject 

 replete with interest, and one which presents a wide field 

 for speculation, both to the physiologist and to the natural 

 historian. By a train of reasoning, interspersed with some 

 ' See the ' Veteriaarian/ for March, 1854, vol. xxvii, p. 156. 



