Studies of North American Bees ly 



peal sutures ; propodeum black with a broad red stripe on each 

 side of the middle 6 



6. Scape, sides of face, clypeus, labrum, legs, sides of abdominal tergites 

 3-6 and disk of tergite 5 bearing conspicuous abundant long 

 black bristles, the hair of occiput and mesonotum pale heavily 

 intermixed with black bristles ; clypeus less strongly punctured ; 

 8.5 mm nigrociliata 



6. Scape, sides of face, clypeus, labrum, cheeks, occiput, mesonotum and 

 sides of propodeum with bright ochreous hair, a very few dark 

 bristles on the sides of the face, legs and the sides of abdomi- 

 nal tergites 3-6, but these all inconspicuous ; clypeus more 



strongly punctured ; 7.5 mm ochrohirta 



7. Apex of fifth abdominal tergite with a broad much depressed 

 velvety area, the lateral sides of which are distinctly, often 

 deeply, pitted, the apical margin transverse ; abdomen dark 

 red, always with large pyriform yellow lateral spots on tergite 

 2, smaller ones almost always on 3, usually smaller subdiscal 

 spots on 4, 5 always with a broad yellow band over and some- 

 times down the sides of the depressed area, nearly encompass- 

 ing it; propodeum wholly red; 8 mm depressicauda 



7. Apex of fifth abdominal tergite without a broad much depressed 

 laterally pitted velvety area 8 



8. Apical margin of tergite 5 somewhat produced mediallj^, so as to form 

 an obtuse angle in profile, not bearing a distinct white terminal 

 fringe, the tergite toward apex more or less distinctly flat- 

 tened or reflexed but not distinctly depressed or pitted, this 

 flattened area more or less distinctly pruinose in certain lights. 9 



8. Apical margin of tergite 5 transverse and bearing a distinct and some- 

 times dense terminal fringe of white hair or tomentum, but 

 bearing no flattened or reflexed area with the surface pruinose. 10 

 9. Tergite 5 with a broad flattened distinctly pruinose apical area, 

 subdivided into a deltoid central and two trapezoidal lateral 

 flattened areas in different planes, and above this pruinose area 

 a yellow bar ; color paler red, the apical margins of tergites 

 1-4 with broad diffused blackish bands and narrowly smooth ; 

 wings less darkened; hind basitarsi red with the hair within 

 golden, broadly edged with black on anterior margin ; 7 mm. 



velutina 

 9. Tergite 5 with a narrow somewhat reflexed and flattened thinly 

 pruinose apical area, not subdivided by flattened areas in dif- 

 ferent planes, the tergite without yellow; color darker red, 

 the apical margins of tergites 2-4 broadly smooth and shining, 

 red; wings distinctly darker; hind basitarsi black witfi the hair 

 within gray very broadly edged with black bristles on anterior 

 margin ; 7 mm angulata 



17 



