WASP GENUS CERCERIS — SCULLEN 421 



basal one medium in size, and the middle one very small but very- 

 acute; antennae normal in form. 



Thorax black except for a yellow band on the pronotum semi- 

 divided at the center and two small patches on the scutellum, which 

 are amber; metanotum black; tegulae smooth, amber, and not ele- 

 vated; enclosure relatively smooth except for a slight medial groove; 

 mesostemal tubercle present but small; legs black basaUy, dark 

 amber on the femora, becoming lighter amber on the apical parts; 

 wings somewhat more clouded than in most species. 



Abdomen entirely black in most specimens except for a broad 

 yellow band on the posterior half of tergum 2; on some specimens 

 small lateral yeUo w spots appear on terga 1 and 3 ; venter black ; 

 pygidium oval with the apical end somewhat narrowed and both 

 ends rounded. 



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

 and pubescence normal. 



Head subequal in width to the thorax, black except large frontal 

 eye patches, interantennal carina, variable amounts on the medial 

 lobe of the clypeus, base of mandibles, and an evanescent spot on the 

 scape, all of which are light yellow; clypeal extension on the medial 

 lobe of the clypeus narrow, subequal in width to the length of the 

 epistomal suture, and with three subequal small denticles; clypeal 

 surface convex, mandibles with one denticle; antennae normal in form. 



Thorax black except for a broken band on the pronotum and divided 

 band on the scutellum; tegulae amber, smooth, and not elevated; 

 enclosure with a light medial groove, relatively smooth but with distinct 

 pubescence laterally; legs amber, coxae and trochanters very dark; 

 wings somewhat clouded. 



Abdomen with little or no yellow on tergum 1; a broad band on 

 the posterior half of tergum 2; narrow yellow lines along posterior 

 margins of terga 3 to 6; venter dark amber; pygidium oval but with 

 the apical end truncate. 



Superficially, both the female and male of C. jlavojasciata Smith 

 look much like C. fumipennis Say, but they are readily separated by 

 the clypeal structure in each case. The female of C. fumipennis Say 

 has no elevated process on the clypeus. The male of the latter has 

 a very narrow extension on the medial lobe. 



Types. — The type female of C. jlavojasciata Smith is at the Uni- 

 versity of Nebraska. The type female of C. natallenus Brimley is 

 at the U.S. National Museum, no. 40792. 



Distribution. — Rare through the Eastern States from South 

 Dakota, Nebraska, and Kansas to the Atlantic Coast States; from 

 Minnesota south to North Carolina. Specimens are as follows: 



