258 U. S. NATIONAL MUSEUM BULLETIN 216 



Manitoba (Riding Mt. Park) ; Maryland (Takoma Park) ; Massachu- 

 setts (Dedham and Woods Hole) ; New Jersey (Moorestown) ; New 

 York (Farmingdale, Orchard Park, and Oswego); Ohio (Barberton, 

 Delaware Co., and Wajme Co.); Rhode Island (Westerly); South 

 Dakota (Harney Peak); Texas (Bosque Co.); Utah (Logan, North 

 Logan, Providence, and "River Heights"); Wyoming (mountains 

 near Sheridan); and Yukon (Canyon Creek). 



Most of the collection dates are from June 17 to the end of August. 

 Dates outside of this range are: April 25 at Takoma Park, Md.; May 

 24, 25, and 29 near Alpine, Ariz.; June 2 in Delaware Co., Ohio; June 

 3 in Riding Mt. Park, Man.; June 4 without locality; June 12 at 

 Decatur, 111.; and September 1 and 3 at Westerly, R. I. 



The species has been reared from Ancylis comptana in Colorado 

 (Rocky Ford); Ohio (Wayne Co.); and Utah (North Logan, Provi- 

 dence, and River Heights). Other rearings are: 3cT, from cinquefoil 

 (Potentilla) leaf roller, Wayne Co., Ohio, June 18, 1944; o\ from 

 Anacampsis agrimoniella , Decatur, 111., June 12, 1918, Barnes; cf, 

 from larva on Populus, Dedham, Mass.; and 9, from "Peronea" on 

 Viburnum, East River, Conn., July 10, 1912, C. R. Ely. 



This species ranges from the Atlantic west to Arizona and Utah, 

 mostly in the upper Austral zone. Adults occur from late spring 

 through the summer. 



50. Exochus mesodon, new species 



Figures 190,p; 196,d 



Male: Unknown. 



Female: Front wing 3.9 to 4.6 mm. long; combined face and clypeus 

 about 0.89 as high as wide, moderately convex in vertical plane, broad 

 and rather weakly convex in horizontal plane; apical angle of inter- 

 antennal process about 80 degrees; median area of frons rather strongly 

 raised and differentiated; median 0.5 of apical margin of clypeus 

 faintly concave; mandible very large, twisted, its apical part rotated 

 from plane of its condyles by about 60 degrees (placing the lower 

 tooth nearer mouth), a little tapered from its base to the base of its 

 teeth, its outer face moderately convex and with a few coarse punc- 

 tures, its lower tooth very short, its upper tooth big and long; second 

 lateral area of propodeum with a few hairs basally and in its apico- 

 lateral corner; front spur of hind tibia about 2.9 as long as wide; punc- 

 tures of second tergite of moderate size and sharpness, very sparse or 

 absent medially, the sublateral punctures separated by about 1.5 

 their diameter. 



Black. Face, lower 0.6 of frontal orbit, triangular spot at top of 

 eye, cheek, adjacent temple, clypeus, mouth parts, front of scape, large 

 hind corner of pronotum, tegula, subtegular ridge, sometimes area in 



