480 ANNUAL REPORT OF NEW-YORB" 



SUPPLEMENT. 



with two grubs in its scrotum, considerably torn and injured by 

 the coarse shot with which it was killed. These grubs are plainly 

 the larva of a bot-fly and not of a flesh-fly. They are placed 

 lengthwise in the scrotum, one forward of the other, producing a 

 tumor nearly an inch and a half in length. Each worm has a 

 cavity for itself, separated from the other, with an orifice towards 

 its hind part, larger than the head of a large pin. Though the 

 worms are probably immature the testicles appear to be entirely 

 consumed, but the parts are so torn that I do not attempt to trace 

 out the exact lesion which they have produced. 



Of these two larv^ that which is lea^t injured is 0.65 long and 0.44 broad. 

 The other is smaller, being only 0.32 broad. They, are oval, moderately 

 depressed, more flattened beneath than above, rounded at one end and some- 

 what pointed at the other, of a coal black color and shining, the whole outer 

 surface being covered with slightly elevated small hard angular granules, like 

 shagreen, but without any projecting spines or teeth-like processes. The skin 

 is remarkably thick and tough like leather, and the rough angular points with 

 which it is covered must produce much irritation in the tumor, especially when 

 the worm moves. It is divided into ten segments by deeply impressed trans- 

 verse furrows, each segment forming a prominent ridge which is most elevated 

 towards its hind edge. Towards the outer side each ridge is cut across by a 

 conspicuously impressed longitudinal line, giving the worm a three-lobed 

 appearance similar to that of a trilobite fossil. On the under side is an analo- 

 gous impressed line, and between these at equal distances along each side are 

 two others less deeply indented. The mouth does not show anj^ jaws or other 

 appendages externally but appears like a simple elliptic orifice placed trans- 

 versely; and the perforation at the opposite end is similar. The specimens, 

 however, are so mutilated that they do not aflbrd a satisfactory examination. 

 The worm is much like the figure in Westwood above referred to. 



July 29th, 1857. I have repeatedly raised the tumbler to see 

 if the Avorm buried last August had hatched, and began to des- 

 pair of obtaining anything from it, when to-day, to my great joy, 

 I find a large fly lying upon its back, dead, upon the surface oJ 

 the dirt in the tin box, with the ends of its wings worn off from 

 flying in its narrow prison, but perfect in every other respect. It 

 proves to be of the bot-fly family {(Estridce) and of the genus 

 Cuterehra of Clark, thus named from two Latin words, cutis tere- 

 hra^ i.e. skin borer or skin piercer, this genus being distinguished 

 by having the bristle of the antennae feather-like or ciliated with 

 a row of fine hairs along each side^ and showing a distinct orifice 



