Studies of North American Bees 27 



Dakota. June 14, 191 1. on Brassica caiiipestris (O. A. Stevens, 

 Nos. 2278, 2285, 228>()), 3 $; do., July 21, 1912, on Apocyniim 

 androseiiiifoliuin (O. A. Stevens, No. 3375). i $; Jamestown, 

 North Uakcna. June 2. 1912, on Seiiecio pursliianiis (O. A. 

 Stevens. No. 3316), i $; \'alley City, North Dakota, August 13, 

 1912. on Chrysopsis ( O. A. Stevens. No. 3628). i $. 



A very distinct species, distinguishable in the female by the 

 immaculate coppery red abdomen, the crested and bilobed meso- 

 scutellum, the coarse puncturation of the vertex and mesonotum, 

 the long hair on sides of propodeum, etc., and in the male by 

 the deeply bilobed mesoscutellum, narrow and strongly notched 

 apex, red areas on mesonotum and pleura, antennal joint 3 about 

 one-half as long as 4, and abdomen with the ground color 

 brownish red with the basal half of tergite i black right across 

 and the apices of the tergites largely blackish. A", adducta 

 Cresson is somewhat allied, but is easily separated by the char- 

 acters given in the table. The female superficially resembles A'. 

 (Noniadula) friescana Ckll., as represented by an autotype in the 

 U. S. National Museum, having the same deeply bilobed meso- 

 scutellum, coarse puncturation, reflexed apical margins of ab- 

 dominal tergites, long hair on propodeum, pale tomentose band on 

 apex of tergite 5, etc., but that species is larger, has antennal 

 joint 3 shorter, sides of tergite 2 with yellow spots and pale 

 yellowish bands on tergites 4 and 5, etc. The anterior coxae of 

 N. bilohata are not spined, but the spine is represented by a 

 blunt tubercle. The six females from North Dakota agree 

 with the t_\pe $ except that four of them have the red brighter 

 and contrasting more with the black markings, and especially is 

 the abdomen of a brighter ccxj^pery red. Three of these four have 

 the red areas of the enclosure encroaching somewhat on the 

 sides of the propodeum. 



Nomada (Nomada) bicrista n. sp. 



S. Lcngtli 8 mm. P.lack, the clypeus, a medio-basal spot on supra- 

 clypeus, broad triangular lateral face marks which are not distinctly 

 separated from the concolorous clypeus and supraclypeal spot by black 

 sutural lines and which extend upward along orbits distinctly beyond 

 level of insertion of antennae, labruni, mandibles except tips, scape in 



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