18 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.48. 



on thorax above. Head ordinary; facial quadrangle about as wide 

 as long, broadening above; process of labrum truncate; clypeus 

 minutely punctured, almost hidden by dense hair; flagellum except 

 first joint bright ferruginous beneath. Third antennal joint short, but 

 considerably longer than the very short fourth and nearly as long 

 as the fourth and fifth combined. Mesothorax dullish, microscopically 

 tessellate; scutellum shining; area of metathorax blue-black, granu- 

 lar, not distinctly defined. Tegulae light rufo testaceous. Wings 

 reddish hyaline; nervures and the large stigma amber color. Basal 

 nervure meeting transverse median. Second submarginal cell nar- 

 row, receiving first recurrent nervure beyond the middle; third sub- 

 marginal long. Tarsi clear ferruginous. Abdomen shining, not 

 punctured; hind margins of segments light reddish, with thin narrow 

 white hair bands, failing in middle on segments 1 to 3. Second 

 segment in middle depressed little more than one-fourth. Apical 

 plate emarginate, a very long fringe of hair extending beyond it. 



In the table this falls in a couplet with A. nigrae, from which it is 

 separated by the uniformly blackish (not reddish brown) abdomen. 



Type.— Cat. No. 18134, U.S.N.M. 



e 16 . Small males with flagellum dark beneath. 



ANDRENA POLYGONI, new species. 



Florissant, Colorado. (T. D. A. Cockerell.) Flying around 

 Riles. July 17. 



Male. — Length, 6 mm. Black, the dull finely striate front blue- 

 black. Pubescence long and white, dark brown on scape and at sides 

 of face. Mandibles bright red at apex, with a prominent inner tooth; 

 process of labrum broad, truncate; clypeus shiny, with distinct but 

 not dense punctures; cheeks broad; flagellum dark brown beneath. 

 Third antennal joint hardly twice as long as fourth; fifth distinctly 

 longer than fourth. Mesothorax dullish, hardly sculptured; area of 

 metathorax dull and granular. Tegulae rufo-piceous. Wings hya- 

 line, slightly brownish; stigma and nervures dark red brown. Basal 

 nervure falling short of transverse median. Second submarginal cell 

 receiving first recurrent nervure well beyond middle. Hair on inner 

 side of tarsi pale yellowish. Spurs cream color. Abdomen shining, 

 with very minute sparse punctures, the surface more or less hoary 

 with pale hair. The hind margins of segments 3 to 5 and the second 

 at sides with well defined hair bands. Apical plate rather narrow, 

 truncate. 



A. polygoni has longer antennae than salicinellina, and long black 

 hair at sides of face (the hair of face in salicinellina and placitae is all 

 white). 



A. vegana has light orange sbigma and nervures, entirely different 

 from polygoni. 



