DIPTERA— ASILID^E. 563 



Family CYRTID^e Loew. 

 ACROCERA Meigen. 



ACEOCERA HIRSUTA. 



PL 5, Pig. 5. 



Ao-ocera hirsuta Scudd., Bull. U. S. Geol. Geogr. Surv. Terr., Ill, 755 (1877). 



A single very fragmentary specimen appears to belong in the neigh- 

 borhood of Acrocera, but is too imperfect to mention with any certainty. 

 The size of the insect, the small head, robust and coarsely haired thorax, 

 stout and abbi-eviated abdomen, indicate a form resembling that of Acro- 

 cera, and the tibia> appear to be destitute of spurs ; but the legs are not 

 very slender and the neuration of tlie fragment of tlie wing does not agree 

 well with Westwood's figure of A. globulus Panz. in Walker's Diptera Bri- 

 tannica. There are, Ijowever, only a few longitudinal veins next the base, 

 disconnected and faint, so that they afford very slight indication of the real 

 character of the wings, and the transverse veins being oIjI iterated nothing 

 can be said of the basal cells. Thorax and abdomen of about equal size. 



Length of body, 4..')"""; head, 0.6°""; height of same, 1.3""". 



Fossil Canon, White River, Utah. One specimen (W. Denton). 



Family ASILID^E Leach. 

 STENOCINCLIS Scudder (Grevb?, myuXk). 



StenocincUs Scudd., Bull. U. S. Geol. Geogr. Surv. Terr., IV, 751 (1878). 



This genus of Asilidaj is founded wholly upon characters drawn from 

 the neuration of the wing, the only portion of the insect preserved. It falls 

 into the group of Dasypogonina, in which the second longitudinal vein ter- 

 minates on the margin apai't from the first longitudinal vein, instead of 

 uniting with it just before the margin. It is not veiy far removed from 

 Dioctria, but differs from it and from all Asilidse I have examined in that 

 the third longitiulinal vein arises from the first before the middle of the 

 wing, instead of from the second longitudinal vein after its emission from 

 the first ; the first longitudinal vein has therefore two inferior shoots, giving 

 the wing a very peculiar aspect, and causing it to differ radically from all 

 other Asilidse ; indeed, it would be hard to know where to look for a simi- 

 lar feature among allied Diptera, unless it be in the anomalous group of 



