206 (ESTKUS BOV1NUS. 



so firm as was the original skin, but is effected by a sort of 

 agglutinating deposit, which afterwards, on the skin being 

 dried and hammered by the tanners, gives way and cracks 

 again in these places, shewing the union to have been of a 

 less perfect nature than the original skin; the succedaneous 

 nature of the repair of broken skin, has been remarked by 

 late physiologists, and we mention this fact as confirmatory 

 of their doctrine. 



" The chrysalis is of a dark brown colour, and in figure 

 somewhat resembles the half of a walnut shell, being nar- 

 rower at one end than the other, and flat on one side, and 

 very rounded and convex on the other. Those which I bred 

 remained in the state of chrysalis from the latter end of June 

 till about the middle of August, when the fly appeared. I 

 have, notwithstanding, observed full-grown larvae in the 

 backs of cows as late as the ninth month, or September, 

 which must have produced their flies as late as November or 

 December, or perhaps not till the ensuing summer. 



" The larva after being immured in the chrysalis a sufficient 

 time, and its soft members dry and in a degree hardened, 

 bursts from its confinement by forcing open a very remark- 

 able triangular lid or operculum, and makes its way out at 

 the small end. 



" The larva at the period of making its way from the back 

 of the beast is weak and tender, and exposed to imminent 

 danger, if on land, of being trod on by the cattle or picked 

 up by birds : if on the water, where the cattle stand during 

 great part of the day at this hot season of the year, it perishes 

 by drowning or becomes the food of fishes. 



" It is worthy of remark, that Eeaumur has stated that its 

 escape from the back of the beast usually takes place at a 

 very early hour of the morning, at two or three o'clock, or at 

 sun-rise ; now, if it be so, it is remarkable that in this way 



