1903.] NATURAL SCIENCES OF PHILADELPHIA. 575 



femora strongly suffused with black behind; middle tibise with a black 

 stripe behind; hind tibise and tarsi strongly suffused with plumbeous 

 behind; spurs yellowish-white; wings fairly clear, strongly darkened 

 on apical margin; stigma dark ferruginous; second submarginal cell 

 much broader above than third; basal nervure ending a considerable 

 distance basacl of transverso-meclial ; abdomen only moderately broad ; 

 first segment with the basal two-fifths (at least) black, the hind margin 

 of the black nearly straight, though more or less crenulated; sides of 

 second to fourth segments with small cream-colored spots, that on 

 second largest, elongated in an antero-posterior direction; fourth and 

 fifth segments with small sublateral cream-colored spots (thus four 

 spots in all on fourth) ; venter red, second to fourth segments with 

 cream-colored marks, second with a large black blotch. 



Hah. — Los Angeles county, Cal. (CoquiUett). One in U. S. Nat. 

 Museum. Allied to N. oregonica, Ckll., but differs by the numerous 

 abdominal spots, the purplish-coppery colors of abdomen, and the 

 absence of a red spot before middle ocellus. 

 Nomada davidsoni, sp. n. 



9. — Length 9 mm.; face, cheeks and sides of thorax with rather 

 abundant white hair; head and thorax rugose, black; eyes gray; facial 

 quadrangle not far from square, but narrowed below; basal half of 

 mandibles, labrum, broad anterior margin of clypeus, and linear (incon- 

 spicuous) lateral face-marks reaching about to level of antenna?, dull 

 yellow; scape black, very hairy; flagellum blackish above and fer- 

 ruginous beneath; third antenna! joint shorter than fourth; tubercles 

 reddish with a yellow spot; pleura with an angular red mark on lower 

 part; scutellum dark red, suffused with black in middle posteriori}^ ; 

 a small orange spot before each anterior corner of scutelhmi; post- 

 scutellum red in middle and j^ellow at sides; metathorax all black; 

 tegulse ferruginous; a reddish patch, becoming yellow posteriorly, be- 

 fore each middle coxa; legs red; anterior and middle femora more or 

 less black beneath, hind femora black behind except at extreme apex; 

 anterior tibise with a black stripe on outer side ; hind tibise with a large 

 black subapical spot on each side ; knees and apices of tibise with more 

 or less distinct cream-colored spots; hind tarsi strongly blackened 

 without; wings moderately dusky, stigma dull ferruginous with a dark 

 brown border; second submarginal cell little narrowed above; basal 

 nervure meeting transverso-medial on the basad side; abdomen only 

 moderately broad, minutely roughened, pale red with large cream-col- 

 ored markings; basal half of first segment black; on the first three 

 segments are pairs of large cream-colored triangles pointing mesad, the 



