REVISION OF ELEODIINI BLAISDELL. 253 



margin truncate to somewhat arcuate, not always well defined from 

 apex internally; angle subrectangular. Apex short, rather coarsely 

 punctate, setse rather short ; fossa fringed with quite long hairs at 

 outer margin, the hairs extending inward along the apical margin 

 of the dorsal plate. 



Ajjpendage short, scarcely as long as the apex, rather stout and 

 conical, rounded at tip and set with rather short setae which form a 

 loose tuft. 



Basal prominences rather strongly developed. 



Superior pudendal membrane not quite reaching to the middle of 

 the dorsal plate and distantly longitudinally rugulose. 



Ventrolateral surfaces (Plate 3, fig. 10) moderately swollen at base 

 and rather broadh^ concave laterally before the apices, glabrous, 

 sparsely punctate and setose in apical moiety, setaj moderately long, 

 especially along the ventral margins of the fossa?. Submarginal 

 groove more or less developed. Internal margins of the valves con- 

 tiguous in basal fourth; genital fissure fusiform and rather wide, 

 with the inferior pudendal membrane visible in basal half. 



The above descriptions are applicable to the greater number of 

 examples in the series before me. The present species is indeed the 

 most variable and polymorphic of any in the genus. 



The large series at my disposal presents a complex of incipient 

 races that are most bewildering. It is not wise nor practicable to give 

 names to these forms and thus burden our faunal lists with names of 

 races which can not be distinctiveh'^ defined. These forms appear to 

 diverge along certain lines of deA^elopment and at the same time to 

 pass directly into one another b}^ the gradual diminution or augmen- 

 tation of characters, as the case may be. It seems to me that it is best 

 to select a few of the heterotypical forms as centers, around which the 

 more incij^ient races ma}" be clustered. 



Undoubtedly dentipes is unusually reactive to its environment, for 

 each geographical region produces some peculiar modification of the 

 typical form, and yet more or less typical examples are taken in the 

 same regions. 



In accordance with the ideas just expressed I shall indicate the 

 following forms for cabinet arrangement : 



Forma pertenuis. — Comparatively small and slender. Pronotum 

 widest at or in advance of the middle ; sides evenly arcuate and con- 

 verging posteriorly, scarcely sinuate to distinctly so before the angles. 

 Legs long and very slender. In the males the hind tibia? are feebly 

 arcvuite in basal half, thence scarcely straight or gradually thickened 

 to apex. 



In one specimen the elytral surface is very minutely reticulately 

 rugulose, punctuation scarcely distinguishable. 



