474 PROCEEDINGS OF THE NATIONAL MUSEUM vol. lie 



clypeal process large, inverted scoop shaped; mandibles with one 

 prominent denticle and a very low divided denticle more basad; 

 antennae normal in form. 



Thorax black except for two elongate patches on the pronotum and 

 the metanotum, which are yellow; tegulae low, smooth, and fulvous; 

 enclosure lightly ridged in the lateral angles and with a light medial 

 groove; mesosternal tubercles absent; legs fulvous; wings subhyaline 

 but clouded. 



Abdomen with broad yellow bands on the first two terga; the band 

 on tergum 1 is semidivided medially; the 3rd and rarely the 4th 

 tergum may show remnants of yellow lines on the posterior border at 

 the lateral extremities; venter immaculate; pygidium with the sides 

 converging to a rounded apical end. 



Male. — Indistinguishable. 



C. clypeata gnarina Banks is very close to C. clypeata clypeata 

 Dahlbom. The size of the former is noticeably larger, the clypeal 

 process more rugged and more rounded on its margins. These 

 characters and the heavy yellow band on the first tergite of the 

 former help to distinguish the females. 



Type. — The type female of C. gnarina Banks, from Vinita, Indian 

 Terr. [Okla.], June 7 (Wickham), is at the American Museum of 

 Natural History, no. 15837. 



Distribution. — Throughout the Western Central States, from 

 Alberta, Canada, south through South Dakota, Nebraska, Iowa, 

 Kansas, Colorado, and into Texas. Limited records are from as far 

 east as Michigan, Ohio, and IlHnois. One specimen is recorded from 

 Georgia. 



Prey record. — None. 



Plant record. — Parsnip (Texas), Polytaenia nutallii (Texas), 

 Zizia aurea (Ohio) . 



53d. Cerceris clypeata prominens Banks, new status 



Figures 78, 159a,b,c 



Cerceris prominens Banks, 1912a, p. 19. — ScuUen, 1942, p. 188; 1951, p. 1010. 

 Cerceris alaope Banks, 1912a, p. 22; 1912b, p. 107.— ScuUen, 1942, p. 188. 



Female. — Length 13 mm. Black with yellow markings; puncta- 

 tion and pubescence average. 



Head slightly wider than the thorax; black except for two large 

 frontal eye patches, patch on the clypeal process, small spot back of 

 compound eye, base of mandible, and the scape, all of which are 

 yellow; clypeal border with two low, broad denticles, between which 

 is a single, medial broad lameUa; clypeal process longer than broad, 

 convex above; mandibles with three denticles, the more apical one 



