Studies of North American Bees 33 



wholly yellow and tergite 7 yellow except at base, otherwise ornamented 

 as in the female; legs red, the anterior and middle knees and the basi- 

 tarsi yellow or yellowish ; antennae black ; 8 mm boreale 



Dianthidium (Anthidiellum) boreale Robertson. 



1902. Dianthidium boreale Robertson, Canadian Entomologist, XXXIX, 



p. 323, c?. 



1903. Dianthidium boreale Robertson, Trans. Am. Ent. Sac, XXIX, p. 



175, c?. 



Found in Sioux county, Nebraska, and probably east along the 

 Niobrara valley to Niobrara, Knox county, where specimens have 

 been collected. Monroe canyon, Glen, and Niobrara, Nebraska, 

 August 9-14, at flowers of Kuhnistera purpurea and Cleome ser- 

 rulata. The species is not common and is represented by only two 

 female and three male specimens. The female, which is unde- 

 scribed, agrees exactly with Cresson's description of D. notatum 

 (Latreille), but tergite 6 is carinate on the apical half and has two 

 yellow spots (wholly black in notatum), the tibiae and tarsi are 

 wholly clear red (exteriorly obfuscated in notatum), and the 

 clypeus is wholly black (broadly yellowish red on lateral margins 

 in notatum). The allotype is from Glen, Sioux county, Nebraska, 

 4,000 feet, August 14, 1906, and was taken on a day following the 

 capture of a male in the same locality. 



Subgenus Heteranthidium Cockerell, 1904 



KEY TO THE NEBRASKA SPECIES 



Female 



Abdominal tergites 1-5 with broad deep yellow bands which are medially 

 attenuated but not interrupted and not emarginate ; clypeus and triangular 

 lateral face marks which extend narrowly above level of antennae, 

 whitish; broad lines behind eyes, four spots on mesoscutellum, large 

 subtriangular areas on antero-lateral margin of mesoscutum which are 

 sometimes reduced to small spots over tegulae, spot on front of tegulae, 

 and spots on bases of all of the tibiae, deep yellow; 13-16 mm. .sebratum 



Male 



Abdominal tergites 1-6 with broad deep yellow bands which are medially 

 attenuated but not interrupted and not emarginate on the disk or but 

 very feebly so on tergites 1-3 ; clypeus, mandibles except tips, and lateral 



33 



