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PROCEEDINGS OF THE NATIONAL MUSEUM 



size and coloring, but the females can be separated easily by the form 

 of the clypeal process, and the males, by the extension on the medial 

 clypeal lobe. 



Types. — The type female of O. robertsonii Fox, from Smithville, 

 S. Dak. (J. T. Aldrich), is at the Philadelphia Academy of Natural 

 Sciences, no. 4755. The type female of C. austrina Fox, from southern 

 Florida, is at the Philadelphia Academy of Natural Sciences, no. 4756. 

 The type female, from Rock Co., Nebr., July 22, 1902, on Helianthus 

 sp. (W. D. Pierce), and the allotype male, from Glen, Sioux Co., Nebr., 

 4000 ft., Aug. 19, 1906 (P. R. Jones), of C. pleuralis H. S. Smith, are 

 at the University of Nebraska. 



Distribution. — Throughout the Eastern States, from Nebraska 

 and Kansas east to the Atlantic States and from southern Canada 

 south to North Carolina, with one record from Texas. 



Prey record. — Rhabdopterus picipes (Ohver), Crypto cephalus 

 notatus Fabricius, Pachybrachys dilatatus Suffrian. All are chrysom- 

 elids, reported by Krombein (1953) from North Carolina. 



Plant record. — Melilotus alba (Kansas), parsnip (Minnesota), 

 Quercus marilandica (North Carolina), Q. virginiana (North Carolina), 

 Liguidambar styraciflua (North Carolina). 



Figures 44-46. — Localities of: 44, C robertsonii robertsonii Fox; 45, C. robertsonii bifidus 

 ScuUen; 46, C. robertsonii emmiliosus ScuUen. 



34b. Cerceris robertsonii bifidus, new subspecies 



Figures 45, 137a,b,c 



Female. — Length 12 mm. Black with yellow and ferruginous 

 markings; structurally like the nominate subspecies C. robertsonii 

 robertsonii Fox except as indicated below. 



Head as in the nominate subspecies except that the clypeal lamella 

 is divided completely to the base. 



