172 NORTH AMERICAN 



Pennsylvania, near Philadelphia, 1. 



From amabills this species differs greatly in its much more dense 

 pronofal punctuation, siiorter second antennal joint, more robust form, 

 and different coloration especially in the color of the under surface. 

 In frctiis the black under surface and excessively pale flavate legs 

 form a very striking contrast. 



A XT II A XI A Esch. 



There are in my cabinet five species of this genus wjiich belong to 

 the group combined by Dr. Horn under the name ceneogaster of 

 Laporte and Gory. I have compared them all with the types in Dr. 

 LeConte's cabinet, but only succeeded in identifying one form, wliicii 

 is strigata Lee; another from California so greatly resembled Dr. 

 LeConte's type of inornuta that 1 determined tlie same to be tliat 

 species. Recently, liowever, in reading the above author's original 

 description of inornata it appears that the front is without short setae, 

 and, since it is described from New York, I have concluded that it 

 must represent a distinct species and not having a representative of it, 

 it is not included in the following study. Strigttta is a very distinct 

 species in shape color and pronotal ornamentation, and it is therefore 

 preserved. The species alluded to above as resembling inornata is 

 quite distinct from striyata ; it approaches very nearly the form 

 figured as ceneogaster by Laporte and Gory, and I have therefore 

 determined to perpetuate this name by its means. The remaining 

 three species not appearing to have been seen by Dr. LeConte or by 

 Dr. Horn, are described as new in order to make the group complete; 

 they cannot unfortunately be identified with any of the species allied 

 to strigata described by Dr. LeConte, either fiom direct observation 

 or by description. 



The sexual characters in the group are strongly marked and lie not 

 onlv in the differences to be oltserved in the sexual organs themselves, 

 which are generally protruded and easily seen, but in the structure of 

 the middle and posterior trochanters, these being acutely toothed 

 behind in tiie males and broadly rounded posteriorly in the females. 



The species are separated primarily according to the pronotal 

 sculpture, this not being the same in any two, but in the subseipient 

 descriptions it will be seen that there are many other points of dis- 

 tinction in the structure and shape of the palpi, antennae, and pro- 

 sternal intercoxal process. The species can also be separated at a 

 Mance by the unaided eye from their general form. Tiie narrow 

 elevated lines forming tlie reticulation are termed rctal lines and tiie 

 spaces limited by tlieni maculae. 



