WASP GENUS CERCERIS — SCULLEN 419 



clypeal process lunar shaped with two oval lamellae attached to the 

 border; mandibles with two prominent denticles, between which is a 

 much smaller but distinct denticle; antennae normal in form with the 

 scape yellow and remaining segments amber. 



Thorax black except for a divided band on the pronotum, two 

 large patches or a divided band on the scutellum, the metanotum, 

 two patches on the propodeum, patch on the mesopleuron (on some), 

 and the tegulae, all of which are yellow; enclosure ridged at a 45° 

 angle to the base; tegulae not elevated and sparsely pitted; mesosternal 

 tubercles absent; legs dark amber basally, becoming light amber on 

 the femora and yellow to amber beyond; wings subhyaline, but 

 lightly clouded along the anterior margins. 



Abdomen: tergum 1 with a small yellow medial patch, tergum 2 

 with a broad band on the posterior half; terga 3, 4, and 5 with deeply 

 emarginate bands quite variable in the amount of yellow; tergum 6 

 with a trace of yellow to the sides of the pygidium; venter dark amber; 

 pygidium broadly rounded basally with the sides narrowing to a 

 smaller rounded apical end. 



Male. — Length 10 mm. Black with yellow markings; normally 

 pitted; clothed with short silvery hairs. 



Head subequal to thorax in width, black except for entire face 

 below antennal scrobes, minute spots back of eyes, basal part of 

 mandibles, and scape, all of which are yellow; clypeal border dark 

 amber with a very narrow extension slightly swollen in the center; 

 hair lobes normal; clypeal surface slightly convex; mandibles with 

 one large, acute denticle; antennae normal in form. 



Thorax black except a widely divided band on the pronotum, two 

 small patches on the scutellum, band on the metanotum, occasional 

 patches on the propodeum, occasional patches on the mesopleuron, and 

 the tegulae, all of which are yellow; tegulae not elevated and nearly 

 smooth; enclosure smooth except for a deep central groove with deep 

 pits along the lateral borders; mesosternal tubercles absent; legs 

 very dark on the coxae, becoming amber on the femora and light 

 amber on the tarsi; wings subhyaline becoming lightly clouded along 

 the anterior margins. 



Abdomen: tergum 1 with a small yellow patch; tergum 2 with a 

 broad band along the posterior margin or largely covering the entire 

 tergum; terga 3 to 6 with a more or less deeply emarginate band; 

 venter dark amber; pygidium broadly rounded basally, tapering to a 

 narrower rounded apical end. 



Specimens of both sexes show considerable variation in the extent 

 of the yellow markings; those from the more northern and eastern 

 areas are inclined to be darker. Those from the southwestern areas 

 may have considerably more yellow. 



