352 CASEY 



sexual characters pertaining to the coriaceous last dorsal, or, 

 perhaps more properly the penultimate dorsal, are varied and 

 valuable in separating species otherwise distinguishable with 

 difficulty, but unfortunately this segment is not often displayed 

 to view. The species are all very local and the singular and 

 isolated group of more or less opaque forms allied to subopacus, 

 seems to be confined to southeastern Arizona. Plaa'dus is the 

 species from Mexico City, said by Mr. Champion to be identi- 

 cal with -pulvinatus^ from Oaxaca, but it does not agree with the 

 description of that species and is undoubtedly different. 



Stictodera n. gen. 



This genus in the second group of the present tribe, possesses 

 a form and facies not unremindful of Cryptadius of the first 

 group, and this resemblance is strengthened by the non-serial 

 elytral sculpture. The body is not quite so broadly oval but the 

 prothorax has the same form, being strongl}'' narrowed from 

 base to apex, with obtusely rounded basal angles. In the form 

 of the tibiae it is quite apart from any other type of the tribe. 

 The frontal emarginations are very minute and the epistoma is 

 extremely feebly produced, with its apex not very broadly but 

 rectilinearly truncate, the eyes large and rather prominent, with 

 the superciliary carinas fine, short and unusually feeble, and the 

 mentum has a small and circularly rounded abrupt sinus at tip. 

 The mandibles are thick but narrowed and deflexed toward tip 

 and are feebly bifid ; they are not properly toothed above, al- 

 though the right mandible has an obtuse dorsal swelling. The 

 metasternum is slightly shorter than the first ventral segment 

 and the body is probably wingless. The single species known 

 thus far may be described as follows : — 



Body stout, oblong-oval, moderately convex, slightly alutaceous, red- 

 brown, the under surface and legs paler and more rufous, gla- 

 brous ; head not very coarsely but strongly, closely punctate, the 

 sides before the eyes unusually short, not much longer than the 

 eye, strongly converging, evenly and moderately arcuate ; pro- 

 thorax short and very transverse, evidently more than twice as 

 wide as long, the deeply sinuate apex about three-fifths as wide 

 as the base, which is transversely truncate and not medially lobed, 

 widest near basal third, the sides rather strongly arcuate basally, 

 becoming strongly converging and less arcuate apically, the punc- 



