WASP GENUS CERCERIS — SCULLEN 471 



yellow spots appearing laterally on sternites 2, 3, and 4; pygidium 

 with sides slightly convex and with the apical end slightly convex. 



C. clypeata Dahlbom and its closely related forms have presented a 

 diflBcult problem to taxonomic workers. Banks was inclined to con- 

 sider slight variations as characters on which to establish new species. 

 On the other hand, some students were inclined to bring together 

 closely related forms that the present writer prefers to keep distinct. 

 The correct identification of some males is still uncertain. Only 

 exhaustive field studies can clear up this problem. 



C. imitator Cresson (new name C. imitatoria Schletterer) , which was 

 described from Illinois, appears to be a male C. cbjpeata Dahlbom, 

 with the band on the second tergite somewhat narrower than on the 

 typical clypeata male. 



The writer has studied the types of C. clypeata Dahlbom at Lund, 

 and he finds the tj'pical forms of this species clearly defined. 



Types. — The type female and allotype male of C. clypeata Dahlbom, 

 labeled "America," are at the Universitets Zoologiska Institution, 

 Lund, Sweden. The type male of C. imitator Cresson, from Illinois, 

 is at the Philadelphia Academy of Natural Sciences, no. 195L The 

 type female and the allotype male of C. chryssipe Banks, from Falls 

 Church, Va., are at the Museum of Comparative Zoology, Harvard, 

 no. 1379 L The type female and allotype male of C. clymene Banks, 

 from Glencarlyn, Va., and Falls Church, Va., are also at the Museum 

 of Comparative Zoology, Harvard, no. 13789. The type male of 

 C. zobeide Brimley and the type female of C. zosma Brimley, both 

 collected at Raleigh by C. S. Brimley, are at the North Carolina State 

 Department of Agriculture, Raleigh, N.C. 



Distribution. — ^Through the Eastern States and southeast Canada. 

 It is common west to eastern Nebraska and Kansas. One female and 

 two males are recorded from Colorado. Limited specimens have 

 been seen from the southeastern Gulf States. 



Prey record. — Balaninus nasicus Say (Peckham, 1898, Wisconsin), 

 Chalepus dorsalis Thunberg (Krombein, 1954, West Virginia), Lema 

 trilineata Oliver (Chrysomelidae) (K. W. Cooper, New Jersey; F. 

 Kurczewski, Virginia); Pissodes strobi (Peck) (K. W. Cooper, New 

 Jersey); Tanymecus con^usus (Say) (Bridwell, Washington, D.C.). 



Plant record. — Acacia (Texas), Ambrosia artemisiaefolia (Ken- 

 tucky), Angelica sp. (Colorado), Asclepias sp. (Connecticut, Massa- 

 chusetts), Asclepias comuti (Illinois), Asclepias incarnata (Illinois) 

 Asclepias sulliventii (Illinois). Asclepias tuberosa (Georgia), Asclepias 

 verticillata (Illinois, Iowa), Aster ericoides (Illinois), Berteroa incana 

 (Massachusetts), Ceanothus sp. (Virginia), Ceanothus americanus 

 (Illinois, New York, Virginia), Chrysanthemum leucanthemum (North 

 Carolina), Cicuta sp. (Virginia), Cicuta maculata (Ohio), cotton 



