■*W CATTLE. 



viding a habitation for its future progeny. It selects the back of th« 

 ox, at no great distance from the spine on either side, and ahghting 

 there, it speedily pierces the integument, deposits an egg in the cel- 

 lular substance beneath it, and piobably a small quantity of some 

 acid, which speedily produces a litlle tumor on the part, and accounts 

 for the apparent suffering of the animal. 



The egg seems to be hatched before the wound is closed, and the 

 larva, or maggot, occupies a small cyst or cell beneath it. The tail 

 of the larva projects into this opening, and the insect is thus sup- 

 plied with air, the principal air-vessels being placed posteriorly; 

 while with the mouth, deep at the bottom of the abscess, it receives 

 the pus, or other matter that is secreted there. A fluid, resembling 

 pus, can always be squeezed from the tumor, and increasing in quan- 

 tity as the animal approaches his change of form. In its early stage 

 of existence the larva is white, like that of most other flies ; but as 

 it approaches its maturity, it becomes darker, and at length almost 

 black. These little tumors form the residence of the larva, and are 

 recognized by the name of warbles. 



The abscess having been once formed, appears to be of little or 

 no inconvenience to the beast on whose back it is found. It cer- 

 tainly does not interfere with his condition, and the butcher regards 

 the existence of these warbles even as a proof of a disposition to 

 thrive. The injury to the skin, however, is another affair, and the 

 tanner would probably tell a different story. The larva, if undis- 

 turbed, continues in his cyst, until the month of June or July in the 

 following year, and then forces itself through the aperture already 

 described, and the accomplishment of which occupies two days. It 

 is soft when it first escapes, but it soon hardens ; and if it is fortu- 

 nate enough to escape the birds, or if it does not fall into the water, 

 which the cattle seem now instinctively to seek, as it were to destroy 

 as many of their enemies as possible, it conceals itself in the nearest 

 hiding-place it can find, where it remains motionless until it changes 

 to a chrysahs, which is speedily effected ; it continues in its new 

 form about six weeks, and then bursts from its shell a perfect fly. 



It is a very singular circumstance, that the escape of the larva 

 from its prison on the back of the ox always takes place in the 

 morning, and between six and eight o'clock. 



Being also exposed to many dangers in its chrj^saline state, it is 

 then covered with a scaly box of great strength, and from which it 

 would seem impossible for it ever to make its escape ; but when its 

 change is complete, and it begins to struggle Avithin its prison, a 

 valve at one end of its narrow house, and fastened only by a slight 

 filament, flies open, and the insect wings its way, fiist to find its 

 mate, and then to deposit its eggs on the cattle in tlie nearest pastures. 



Some farmers are very careless about the existence of these wai> 

 bles ; others very properly endeavor to destroy the grub that inhajj- 



