224 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.43. 



TENTHREDO ^LABIDIA) SUBNIGRICEPS (Rohwer). 



Allantus subnigriceps Kohwer, Can. Ent., vol. 41, 1909, p. 149, female. 



Type.— C&t. No. 14271, U.S.N.M. 



Nevada; New Mexico; Washington; California. 



TENTHREDO (LABIDIA) OPIMUS OPIMUS (Cresson). 



Allantus opimxis Cresson, Trans. Amer. Ent. Soc, vol. 8, 1880, p. 15, male and 



female. 

 Lahidia Columbiana Provancher, Addit. fauna Canada Hym., 1886, p. 21, male. 



TENTHREDO (LABIDIA) OPIMUS COLORADENSIS, new subspecies. 



Separated from the typical opimus by the following characters: 

 Hind femora black; dorsal walls of the ocellar basin sharply defined; 

 oceUar basin rather longer, striato-granular; slightly smaller and 

 markings paler. Female. Length 8 mm. 



Short Creek, Colorado. One female. 



Type.— Ca.t. No. 14599, U.S.N.M. 



TENTHREDO (LABIDIA) ORIGINALIS (Norton). 



Allantus originalis Norton, Trans. Amer. Ent. Soc, vol. 1, 1867, p. 261, female; 

 Norton, Catalogue, p. 123, female. 



Labrador; New Hampshire. 



TENTHREDO (LABIDIA) ALIENATUS, new species. 



Readily separated from the foregoing species of Lahidia by the obso- 

 lete ocellar basin. 



Female. — Length 9 mm. Clypeus nearly impunctate, deeply arcii- 

 ately emarginate, lobes broadly rounded apically; supraclypeal and 

 antennal fovese confluent; supracl3rpeal area convex, sparsely punc- 

 tured; middle fovea large, deep; ocellar basin obsolete, but the area 

 striato-granular; antennal furrows obsolete; postocellarfuiTOW poorly 

 defined; postocellar area more coarsely sculptured than the rest of 

 the vertex, defined laterally by furrows; postocellar line subequal 

 with the ocelloccipital line; antennas eight-jointed, the last three 

 joints not sharply defined; prescutum more closely punctured than 

 the scutum; scutellar lobe closely punctured; stigma nearly straight 

 below, apex oblique; sheath narrow, straight above, truncate apically, 

 oblique below. Black; clypeus, labrum, mandibles (apices piceous), 

 hne on the dorsal and ventral margins of pronotum, spot on scutellum, 

 metepisternum, narrow apical margins of abdominal segments and 

 propodeum, four anterior femora beneath, four anterior tibiae (except 

 dorsal apices), four anterior tarsi except a line above, hind tibiae 

 except apices, yello wish- white ; pubescence black, wings hyaline, 

 slightly 3'ello wish; venation dark brown, stigma and costa yellowish. 



