166 Descriptions and Records of Bees. 



warm reddish ; antennae black ; vertex dull, not punctured ; 

 mesothorax dull, without any distinct punctures ; area of 

 metathorax dull, without plicae ; teguke piceous. Wings 

 hyaline, the large stigma and nervures dull ferruginous ; 

 second s.m. broad, receiving first r. n. before middle. Legs 

 black, with pale hair, that on inner side of hind basitarsi 

 very pale ochreous. Abdomen broad, dull, with a slight 

 satiny gloss, impuuetate ; second segment feebly depressed 

 about two-fifths ; white hair at sides of first segment, and 

 segments 2 to 5 with long white hair-bands, very weak in 

 middle of second, apical hair slightly brownish. 



Indian Creek, Nampa, Idaho, at flowers of willow, 

 April 26, 1916 (Gohlie McGlothlen). 



Easily known from A. niyritarsis,, V. & C, and A. brachy- 

 carpa, V. & C, by the dull abdomen, with the surface micro- 

 scopically cancellate. It is nearest to A. nudlscopa, Yier., 

 and A. nnistelicolor, Vier., but is smaller, with reddish facial 

 foveas and wings not reddened. These two species have not 

 yet been fully described, but I have specimens determined by 

 Viereck. The hind basitarsus of opacissima is slender, only 

 about half as broad as the tibia at end, a character of nudl- 

 scopa (syn. angustitarsata, Vier., fide Viereck in lift.) rather 

 than muslelicolor. On the other hand, the dull minutely - 

 roughened clypeus is that of mustelicolor rather than nudl- 

 scopa. The paler, dark margined stigma also distinguishes 

 the new species from my example of nudiscopa. 



Andrena politissima, sp. n. 



5 . — Length a little over 9 mm. 



Black, shining, the head and thorax with long pale hair, 

 distinctly ochreous dorsally ; clypeus with very long hair; 

 facial quadrangle broader than long ; process of labrum 

 narrowly truncate ; malar space short but distinct ; clypeus 

 shining, with distinct rather dense punctures, no smooth 

 median line ; facial fovea 3 , rather broad, very pale ochreous ; 

 antennas black, third joint little (about 4 per cent.) shorter 

 than next two combined; mesothorax and scutellum shining, 

 with strong scattered punctures ; postscutellum prominent 

 in middle; area of metathorax distinctly defined, dull, with 

 a median ridge and rather weak though large oblique lateral 

 plicae, giving a fluted effect; tegulae piceous. Wings dusky, 

 greyish, yellowish basally ; stigma and nervures dusky red- 

 dish; second s.m. about as broad as high, receiving first r. n. 

 about middle. Legs black, with pale hair; middle and hind 



