Studies of North American Bees 39 



red, the knees slightly yellowish. Abdomen paler red than the thorax, 

 the basal half of tergite i black with a large triangular red median area 

 connected narrowly with the concolorous apical half of the tergite, 

 tergites 2-6 red with more or less of a blackish suffusion on the middle 

 of the depressed apical margins of the segments, and the tergites with 

 bright yellow maculations as follows : i with two oblong lateral spots, 2 

 with large subpyriform lateral spots, 3 with large oval lateral spots, 4 

 and 5 with basal bands more or less distinctly interrupted on 4, and 6 

 with a broad transverse band, medially emarginate above. On the middle 

 of each lateral side the spots or bands are slightly emarginate on the pos- 

 terior margin, especially on 4 and 5. Apex dark red, strongly bifid. 



Allotype. — Bellevue, Sarpy county, Nebraska, April, (^. 



Closely resembles the (^ oi N. cressonii Rob., but is darker red 

 with less black on the propodeum, flagellum above, legs, etc., less 

 yellow on the anterior legs and face, the scutellum more acutely 

 bilobed, etc. The cressonii compared is a specimen from Indiana 

 in the U. S. National ]\Iuseum collection. 



Nomada (Nomada) velutina n. sp. 



?. Length 7 mm. Light red, the cheeks behind, an ocellar spot, a broadly 

 oval spot about bases of insertion of antennae which extends downward 

 in the clypeal sutures and nearly isolates the supraclypeus, prothorax 

 except collar and a spot above coxae, large spots on mesosternum, meta- 

 pleura, the adjacent extreme edges of the propodeum, a broad median 

 line on mesoscutum, depressed sides of mesoscutellum and metanotum, 

 a diamond-shaped spot on propodeum just beneath the apex of the 

 enclosure, the basal half of first abdominal tergite, the apical margins of 

 tergites 1-4 (broadly and suffusedly, without great contrast as in the 

 nigrocincta group), all of the femora on under half or more of base, 

 and a line on posterior face of hind tibiae, black or blackish. Antennae 

 red, joint 3 about two-thirds as long as 4, the scape with erect pale 

 ochreous hair. Thorax practically devoid of hair, the few short, scattered 

 hairs all white. Tubercles and tegulae testaceous. Wings uniformly 

 faintly clouded, except for a clear spot just beyond and beneath sub- 

 marginals, the nervures and stigma dark brown, the basal nervure slightly 

 but distinctly basad of transverso-medial nervure. Abdomen red, with 

 black or blackish marks as described, tergite 2 with small but conspicuous 

 yellow pyriform spots laterally, 3 and 4 immaculate, 5 with a broad bar 

 of yellow immediately above a flattened area which involves the apical half 

 of the tergite, which has the apical margin obtusely angulate in profile. 

 The flattened apical half of the tergite is subdivided into a median well- 

 defined deltoid area, the apex of which attains the apical margin of the 

 tergite at the apex of the angulation, and on each side of this deltoid area 



39 



