BEES OF BOULDER COUNTY, COLORADO 243 



DIALICTUS Robertson 

 Like the species of Halictus with green or blue head and thorax, but with only two 

 submarginal cells. The table is based on the females. 



Tegulse testaceous (Boulder, fls. Phacelia) anomalus Robertson 



Tegulae dark ^' 



I. Bluish; abdomen with metallic luster ; face narrow (Las Vegas, N. M.) 



theodori Crawford* 



Greenish; abdomen without metallic luster; face broader (Boulder, fls. DrymocalHs) 



occidentalis Crawford 

 I have not now access to the type of D. theodori, but it occurs to me as just possible 

 that it is an aberration of Halictus semicaruleus. 



AUGOCHLORA Smith 

 Comparatively large and robust; hind margin of second abdominal segment 



finely ciliate (Boulder) fervida Smith. 



Much smaller, not so robust (Boulder, fls. Hydrophyllum, May 18. Ckll. S. 

 Boulder Canyon, fls. Grindelia, Aug 9, W. P. Ckll.) . conf usa coloradensis (Titus) 

 A variety of the $oi A. conjusa coloradensis, with the flagellum dark, was taken in 

 S. Boulder Canyon, fls. Aster lavis, Aug. 9. {W. P. Ckll.) 



AGAPOSTEMON Smith 



Females ^' 



Males 5* 



1. Abdomen green or bluish ^' 



Abdomen black 4- 



2. Meso thorax with punctures of two sizes 3- 



Mesothorax uniformly punctured or roughened (Colorado etc.) splendens Lep.* 



3. Base of metathorax without a distinct triangular inclosure, the longitudinal ndges 



strong (Boulder, fls. Carduus oc.) texanus Cresson 



Base of metathorax with a more or less evident triangular inclosure, the longitu- 

 dinal ridges weaker (Boulder, April, fls. Claytonia lanceolata and Pulsatilla hirsu- 

 tissima) texanus subtiUor Ckll. 



4. Larger, 12-14 mm. long; head and thorax bluish (Boulder, fls. Carduus, W. P. 



Ckll) coloradensis Crawford 



Smaller; head and thorax green (Boulder, fls. Carduus, Linum lewisii and Trade- 

 scantia universitatis) viridulus (Fabricius) 



5. Hind femora greatly swollen or incrassate splendens Lep.* 



Hind femora only slightly or not swollen . . 



6. Last ventral segment with a median carina viridulus (Fabricius) 



Last ventral segment without a median carina texanus Cresson 



The above table is adapted from that of Crawford. The males have the abdomen 

 banded with black and yellow, and look very unUke the females. 



NOMIA Latreille 

 Abdomen black, with light pearly-green bands (Colorado etc.) foxii Dalla Torre* 

 Abdomen without such bands; tibiae of male ferruginous; teguls amber-color 

 (Fort CoUins, fls. Solidago, August) bakeri Ckll.* 



