SG4 HYMENOPTERA OF AMERICA. [PART I. 



Head very densely punctured ; thorax closeiy shagreened. 

 Post-scutel truncate, having an elevated posterior face ; meta- 

 thorax quite rounded, posteriorly more flattened than excavated, 

 strigose. Abdomen quite ovate, polished; the first segment cup- 

 shaped, anteriorly somewhat rounded truncate. 



Black; the body all bristling with long fulvous hair, especially 

 on the head and thorax ; that of the abdomen shorter and more 

 gray. A frontal transverse mark, a post-ocular spot, and the 

 margin of the middle of prothorax, sulphur-yellow. Wing scales 

 testaceous, black at base. A regular yellow fascia on the seg- 

 ments 1-5 of the abdomen ; the fasciae 3-5 abbreviated. Feet 

 black ; knees, tibia?, and tarsi, yellow (%). Wings subhyaline. 

 The 2d recurrent nerve falling nearly into the 3d cubital cell. 



9. Unknown. 



%. Mandibles yellow, having near the extremity a 'strong 

 notch, followed by a stout tooth. Labrum }^ellow. Clypeus 

 wider than long, yellow, terminating in two long teeth, separated 

 by a wide notch in the form of an arch. Antennae very large, 

 thick, black above, yellow beneath ; the last six joints flattened 

 and rolled up into a spiral, quite black. Intermediate femora 

 strongly bidentate beneath; their first tooth slender and elongate, 

 in form of a broken spine; the intermediate shorter and more 

 widely compressed, the third forming a sort of lamella attenuated 

 up to the extremity of the femur, these teeth separated by wide 

 notches. Intermediate tibiae apparently notched at base and 

 tumefied from the middle. The 6th segment slightly margined 

 with yellow. 



Bess. a. diff. — This is the only American representative known 

 of the subgenus Epiponus. Compared with the European species, 

 it quite resembles 0. spinipes, except that the 3d tooth of the 

 intermediate femora is not quite so much developed. It might 

 be 0. spinipes, transmigrated and modified. 



APPENDIX TO THE GENUS ODYNERUS. 



1. Species sedis incertde. 



The following species I cannot introduce in the classification 

 of the genus, their forms not having been sufficiently described. 



