180 GEORGE H. HORT, M. D. 



Fourth. — Tibiae toothed at middle % . 



The characters of least importance in groupinj^ the species are- 

 found in the form of the clypeus and the armature of the head. 

 With one exception (hiarmatus) the upper surface of the head is 

 simihir in the sexes. 



The species may possess stridulating power, the surface of the 

 propyj^idium is finely alutaceous and with a pearly lustre, and this 

 is probably the ori];an for the above purpose in conjunction with the 

 edge of the apical elytral margin. 



Tbe elytral stria present a peculiarity worthy of notice. In all the 

 neighboring genera in our fauna the sutural stria is parallel with the 

 margin, while the other striaa are slightly oblique; in OchoJpcux, 

 however, the sutural stria is also oblique and becomes very closely 

 approximated to the sutural margin at its apical third. 



The following table is presented as the result of the grouping of the 

 characters above-mentioned. 



Prosternum lobed in front. 



Mentum in the form of a wedge, elevated in front with the basal face 

 longitudiinally concave. First joint of hind tarsus long, stout anil 

 arcuate. Clypeus hemihexagonal, anterior edge double, front without 



elevations peff oralis. 



Prosternum not lobed in front, first joint of hind tarsus long but slender. 

 Mentum as long or longer than wide, more or less impressed longitudinally. 

 Mentum longitudinally impressed in its entire length; bead with or 

 without ridges, but never with an acute median tubercle. 

 Posterior tibiae of male with an acute tooth at middle. 



Posterior femora of male with aa unciform dilatation of the 

 articular plate. 



Clypeus broadly hemihexagonal, witli a crescentic ridge 

 near the aj)ical margin, front with short transverse 



carina luusciilus. 



Posterior femora of male without tooth at the tip. Clypeus 

 broadly hemihexagonal, anterior margin double; head with- 

 out tubercles or ridges ..siiuple.v. 



Posterior tibiae of male slightly dilated at middle. 

 Posterior femora of male without apical tooth. 



Clypeus broadly rounded, anterior margin double; head 



without ridges I'lkei.. 



Posterior tibifB of male not differing from that of female c.xce{)t 

 being broader and more fimbriate. 

 Articular plate of hind femora prolonged nearly one-third the 

 length of the femur, terminating abruptly with an acute angle, 

 similar in the two sexes. 



Clypeus broadly rounded, lateral angles elevated into an 

 acute tubercle %, or plane 9 biariuatiis. 



