WHEAT FLIES DECEIVING. 301 



black band towards their bases (as shown in the separate illustration of the leg, 

 fig. 5 a), and the middle ones having a narrower faint blackish one; the tips of the 

 feet being also black. Bristle of the antenna} black. A slight transverse tawny- 

 yellow line above the base of each antenna?. The two vcinlets of the wings are 

 distant from each other thrice the length of the second or outer veinlet. 



Two of these flies were enclosed in a vial when captured. Adhering to one of 

 them was a small bright red mite, which is parasitic upon these flies. This fly died 

 in about three hours, the other remaining brisk and lively twelve hours afterwards, 

 when it was removed for examination. 



The yellow-hipped Oscinis, 0. coxendix , is 0.07 in length to the tip of its ab- 

 domen, and 0.10 to the end of its wings. It is black with a white face and buff 

 yellow front shaded to blackish on the crown, where is a polished deep black semi- 

 circular mark, its concave side facing backward. Its anterior hips are testaceous 

 yellow. The veinlets are less than twice the length of the second from each other. 



The thick-legged Oscinis, O. crassifemoris, is the same size with the last, 

 and is black with a white head and the thorax with a gray reflection. The last 

 joint of the antenna? with its bristle is black. The legs are pale yellow, the tips of 

 the feet black. The veinlets are so near each other that they are almost united. 

 In the female the abdomen is egg-shaped and polished, its apex drawn out into a 

 long sharp-pointed ovipositor. The middle and anterior thighs are rather short 

 and thick, the hind ones longer and cylindrical. 



The fly figured, plate 1, fig. 3, is a much larger species pertaining 

 to another group. It occurs in abundance upon the heads of wheat 

 the latter part of June. This is the species which was currently re- 

 garded in the circle of my acquaintance as being the fly from which 

 the little yellow maggots, the larvse of the wheat midge, proceeded, 

 until I came to investigate this subject,and discovered in our coun- 

 try the real culprit (Cecido7iiyia Tritici) described by Mr. Kirby. 

 As I have had occasion repeatedly to allude to this popular mis- 

 take, and this fly has received no name, as I have been able to 

 discover, by which it may be specified, I here present a name 

 and description of it, and also of another common species closely 

 related to it. I as yet know nothing of their habits, beyond the 

 fact that they are both numerous, hovering over and alighting 

 upon the heads of wheat at the time they are in flower. 



The deceiving wheat fly, Hijlemyia d'Ceptiva, is a quarter of an inch in length 

 to the tip of its wings. It is ash gray, with black legs, antenna? and feelers. Ab- 

 domen with a row of longditudinal brown-black spots forming an interupted stripe 

 along its middle. Thorax in a particular reflection of the light showing a brown 

 stripe anteriorly and on each side of it a brown spot. A tawny yellow spot upon 

 the front, more conspicuous in the females, and passing into a black stripe upon 

 the top of the head. 



The similar wheat fly, Hymelyia similis, resembles the preceding, but is a 

 size smaller, measuring 0.22 in length, and of a paler shade of ash gray, with the 

 tawny yellow spot upon the front replaced by black, and is destitute of the brown 

 stripe and spots upon the thorax. 



