538 PROCEEDINGS OF THE ACADEMY OF [1893. 



than in Davisii; scutellum strongly convex ; upper surface of meta- 

 thorax coriaceous or finely granulated, with a longitudinal, medial, 

 impressed line, and at the extreme base with a transverse series of 

 short stria?, the rnetapleura? delicately striated; legs tolerably spinose; 

 pygidial area strongly and sparsely punctured, shorter and broader 

 than in Davisii (its length is about one-quarter greater than its width 

 at the base). Black ; anterior tibia? in front yellowish ; mandibles 

 medially, tegula? and tarsi reddish testaceous ; segments of abdomen 

 testaceous on apical margins ; front, face, clypeus and thorax, more 

 or less, clothed with silvery pubescence ; abdomen with a sparse sil- 

 very pile ; wings hyaline, iridescent, nervures testaceous ; distance 

 between the first recurrent nervure and the base of the second sub- 

 marginal cell on the cubital vein greater than the length of the peti- 

 ole of the second submarginal cell. Length 6-7 mm. 



Colorado. Closely resembles Davisii but is distinct by the arma- 

 ture of clypeus, shape of pygidium and color of mandibles and legs. 



3. — Plenoculus Cockerellii n. sp. 



9 . — Anterior margin of clypeus rounded-out, not emarginate or 

 dentate; first joint of flagellum distinctly longer than the second; clor- 

 sulum and scutellum minutely punctured, the latter strongly convex; 

 metathorax coriaceous, or finely granulated, with a longitudinal, 

 medial, impressed line above, and without the series of transverse 

 stria? at base, metapleurae shining ; legs tolerably spinose, the tarsal 

 comb rather strongly developed ; pygidial area strongly and sparsely 

 punctured, short and broad, its lateral margins better developed 

 than in either of the two other species. Black; abdomen entirely red; 

 mandibles, except apex, ferruginous; tegulse, inner side of hind tibia' 

 and base of the anterior pair, yellowish; a large spot on the four an- 

 terior femora beneath near the apex, white ; hind tibia 1 on outer side 

 and the tarsi, reddish-testaceous; wings hyaline, iridescent, nervures 

 testaceous; distance between the first recurrent nervure and the base 

 of the second submarginal cell on the cubital vein less than the length 

 of the petiole of the second submarginal cell; the third transverso- 

 cubital nervure on its lower portion bulges out towards the apex of 

 wing. Length 6 mm. 



Las Cruces, New Mexico (T. D. A. Cockerell). A very pretty 

 and distinct species, which may easily be recognized by its coloration. 



