43 



OEE-KILLKR. LEOS AND WINaS DESCniBED. DBLIGnTS IN THR SUKSniNK. 



over a tenth of an inch in length, of a tawny yellow color, polished and 

 shining, project from the blunt end of the bodj'. These are termed a three- 

 pronged ating in the above letter. But the magnifying glass shows they 

 are abruply cut off at their ends and do not taper to a sharp point capable 

 of piercing the human skin. The legs are long and stout and of a pale, 

 dull yellowish color. The thighs in the males are chestnut brown, and on 

 their anterior aides they are dull black in both scxeis, the hind pair being 

 entirely black, except a stripe of dull yellowish along the under side. The 

 hind shanks also are frequently black on their anterior sides The legs 

 are covered with gray hairs and have several black bristles in rows running 

 lengthwise. In the males the four anterior shanks and feet have the hairs 

 yellow, and on the feet the bristles also are of this color. The ivinr/s are 

 long and narrow, and in repose are laid flat, one upon the other. They are 

 transparent, with a smoky tinge, and are perceptibly darker at their tips. 

 Their veins are black, except the parallel ones in the outer border, wliich 

 are dull yellowish brown. The broad pane or panel at the tip of the wings, 

 ■which is technically termed the second sub-marginal cell, rapidly narrows 

 as it extends forward into the wing, for two-thirds of its length, the remain- 

 ing third being quite narrow, with its opposite sides parallel. Along the 

 vein which forms the boundary of this cell on its outer side, is a percepti- 

 ble smokincss, which is not seen along the sides of the other veins. This 

 vein is slightly bent in the form of a bow two-thirds the length of the cell, 

 when it abruptly curves in the opposite direction, and is then straight the 

 remainder of its length. A veinlct connects it to the next longitudinal 

 vein, thus forming between the anterior portions of these two veins a third 

 sub-marginal cell, which is very long and narrow. 



The arrangement of the veins in the wings, forming three submarginal 

 cells as above described, induces me to refer this species without hesita- 

 tion to Macquart's genus Trupanea; although the silvery white spot on the 

 tip of the male abdomen would indicate it to pertain to the genua Erax, as 

 restricted by the same author. 



The brief note of our correspondent gives us no particular information 

 upon the habits of these flies or the manner in which they attack and kill 

 the bees. But the members of this Asilus group are all so similar in their 

 habits that we are aware what the operations of this species will be. And 

 some account of the habits of these insects may be of sufficient interest to 

 the reader to be here related. 



These Asilus flies, like some other of our most rapacious insects, parti- 

 cularly delight in the hot sunshine. One or two evidences of thi.s may here 

 be adduced. 



Plies of this kind are rare in my vicinity. I suppose I might hunt for 

 days without being able to find a living specimen. And I do not recollect to 

 have ever seen one of them, hitherto, about my house or yard. Three days 

 ago, however, when occupied in preparing this account, I casually spread 

 some damp newspapers before my door to dry in the hot sun. On stepping 

 out to gather up these papers I was most agreeably surprised to sec 

 alighted upon one of them and basking in the sun, what proves to be a 



