ABT. 16 NORTH AMERICAN ICHNEUMON-FLIES CUSHMAN 47 



more or less reddish, hind femur varying from black to ferriginous, 

 in the latter case the front and middle femora also largely ferru- 

 ginous in front; wings uniformly infumate. 



Male. — Differs from female principally as follows : Anterior orbits 

 white, narrowly on frons, broadly on face, clypeus, and mandibles 

 white; antennae immaculate; collar, humeral margin of pronotum, 

 tegulae, subalar tubercle, scutellum and its basal carinae, underside 

 of front and middle coxae and trochanters, and joints 2-4 of hind 

 tarsus white; propodeum more coarsely sculptured, apical carina 

 more nearly complete, interrupted only by a narrow median f oveolate 

 gi'oove; abdomen narrower, subcompressed toward apex; wings 

 longer, hyaline. 



The type of yromytus is from Illinois, that of atnericanus from 

 Maine, and that of hrevipennis from Canada. The United States 

 National Museum specimens are as follows: Ames, Iowa, August 13, 

 1925, one female; Pringle, S. D., July 15, 1924, one female; Col- 

 orado, C. F. Baker collection, one female; and two males without 

 labels. The Colorado specimen is a homotype (Cushman) of avieri- 

 canus and one of the males has been compared by Cushman with the 

 type of prcytnptus. 



MESOSTENUS MELANURUS. new species 



Very distinct because of its broad temples, short, thick thorax, 

 immaculate antennae, and polished abdomen. 



Fenwle. — Length, 7 mm. 



Temples nearly as broad as eyes, very strongly convex, distinctly 

 punctate; frons and face punctate, more densely so medially; eyes 

 parallel ; malar space very nearly as long as basal width of mandibje ; 

 antennae apparently nearly as long as body (extreme apices gone), 

 first joint of flagellum about a third longer than second, others 

 gradually, successively shorter. Thorax but Jittle more than a half 

 longer than deep, dorsally and ventrally polished and rather sparsely 

 punctate, laterally opaque and finely, very densely, almost retic- 

 ulate, punctate ; propodeum very short, apical carina obsoletely inter- 

 rupted medially, ascending much more closely than usual to basal 

 carina, hardly more prominent at angles, basal areas polished and 

 sparsely punctate, middle areas obliquely rugulose, apical area 

 reticulate rugulose ; areolet elongate, recurrent antef ureal ; nervulus 

 antef ureal; abdomen polished, almost impunctate, postpetiole much 

 shorter beyond spiracles than broad, second tergite hardly a half 

 longer than broad at base; sheath nearly as long as abdomen; ovi- 

 positor slender, slightly compressed, decurved, elongately subsagit- 

 tate at apex. 



