531 jMr. T. D. A. Cockerell — Descriptions and 



white hairs behind ; small joints of middle tarsi moderately 

 thickened ; posterior basitarsi only moderately broadened. 



Hab. Lehi, Utah, Sept. 9,1905 {W. A. Hooler). U.S. 

 National Mnsenm. 



Snpcrficially just like M. comafa, Cress. ( ? from Albu- 

 querque, New ^lexieo ; Snow), but easily distinj^uishcd by 

 the coarse black lair on apical part of abdomen above. In 

 this feature it resembles M. manifesta, Cress., which is much 

 smaller and otherwise different. 



Megachile innupta, sp. n. 



? . — Length 12 mm. 



Black, robust, with rather abundant silky greyish-white 

 hair, forming entire and conspicuous bands on abdominal 

 segments 3 to 5 ; clypeus with thin inconspicuous hair; 

 sides of vertex with a small amount of black hair ; hair of 

 thorax above entirely clear white ; first two abdominal seg- 

 ments Avith copious white hair, third with thin pale hair in 

 transverse sulcus, and short black hair between that and the 

 apical band, fourth and fifth (except the bands) with short 

 black hair, the fourth with a little pale basalh^, sixth with 

 thin and rather short, erect, pale hair; ventral scopa white 

 basally, but clear ferruginous on the last two segments. 



Mandibles broad, quad ridentate, with golden hairs from the 

 lower border ; clypeus strongly and densely punctured, with 

 a thick, shining, essentially straight lower margin, but the 

 sides of the margin broadly lobed or extended beyond the 

 level of the central part; antennae black; sides of vertex 

 with large scattered punctures on a shining ground; meso- 

 thorax densely punctured, smooth and shining in the anterior 

 middle ; no lines of hair or sutural band ; tegulae rufo-piceous. 

 Wings hyaline, faintly dusky, nervures dark rufo-fuscous, 

 h. n. falling short of t.-m. ; anterior tarsi very thick, with 

 long glittering white hairs behind; small joints of middle 

 tarsi remarkably thick and short ; hind basitarsi much 

 broadened ; all the claws with a well-developed basal tooth. 

 Abdomen finely punctured, sixth dorsal segment in profile 

 gently concave, without a distinct lip ; when the abdomen 

 is seen from above, there are no conspicuous dark hairs pro- 

 jecting laterallv from the apical segments. 



Hab. Pueblo*, Colorado, Aug. 10, 1907 (G. M. Hite). 

 This looks much like j\l. nupta, Cress., but is easily 

 separated by the lack of a distinct lip on the last dorsal 

 segment, the much more swollen anterior tibiae, and the long 

 hair on anterior tarsi behind. M. nupta has still shorter 

 middle tarsi, the basitarsi being shorter. The clypeal 



