50 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.48. 



tibiae white; on inner side of hind tarsi pale golden. Abdomen 

 dullish, without punctures, all the segments with broad entire white 

 hair bands. Hair at apex stained with brown. 



In the key, this falls in a couplet with A. complexa, and is separated 

 thus: 



Abdominal segments greenish ; pubescence pale, whitish complexa. 



Abdominal segments black ; pubescence yellowish townsendi. 



b 70 . Much smaller species than under a 70 . 



a 72 . Species like A. hirticincta, with long yellow hair; the broad entire abdominal 

 bands as wide as the intervals between them. 



ANDRENA COSTILLENSIS, new species. 



Colorado. No. 2294. 



Female. — Length, 9 mm. Black, with abundant long hair, which 

 is bright yellowish on thorax above, elsewhere paler, and beneath 

 inclining to grayish white. The caudal fimbria pale, like the very 

 thick and broad abdominal bands. Facial quadrangle broader than 

 long; process of labrum broad, shallowly emarginate; clypeus strongly 

 and rather closely punctured, with rather indistinct median smooth 

 line. Facial foveae seen above pale ocherous, occupying more than 

 half the space between antenna and eye, their lower end level with 

 top of clypeus, and separated only by a shining line from the eye. 

 Flagellum dark reddish beneath. Third antennal joint fully twice as 

 long as fourth; fifth about equal to fourth. Mesothorax dullish, 

 very hairy. Anterior half of scutellum shining; area of metathorax 

 granular, defined only by absence of hair. Tegulae shining piceous, 

 very hairy. Wings hyaline, slightly dusky, stigma light amber, 

 nervures fuscous; basal nervure meeting transverse median; first 

 recurrent nervure joining the nearly square second submarginal very 

 near its end. Third submarginal long. Legs distinctly brownish; 

 spurs cream color. Middle basitarsi remarkably broadened and 

 flattened. Abdomen dullish, hardly punctured, second segment in 

 middle depressed about two-fifths. 



Also collected in the Costilla Mountains, New Mexico, August 16, 

 1899 (Miss Mize), and at Eldora, Colorado, August 18, 1910, at 

 flowers of Grindelia and Erigeron, by T. D. A. and W. P. Cockerell. 



In the key, this falls in a couplet with A. apacTieorum Cockerell, 

 and is separated thus: 



Scutellum dull; fimbria brown apacheorum. 



Scutellum shining, partly polished; fimbria ochreous costillensis. 



Type. — Entomological collection of the University of Nebraska. 



o 72 . Not as under a 72 . 



a 73 . Without distinct light abdominal bands. None of the species very small. 



a 74 . Hair of thorax short; grayish white; wings unusually short. 



