AMERICAN COLEOPTERA. 139 



terminal bristles. All specimens seen but one are females, these 

 differing from the male in their somewhat smaller eyes, shorter 

 antennal club, and in the fifth ventral segment being strongly 

 tuberculate before the apex. 



IK VOIt 1 1 S Thomson. 



Men turn transverse, trapezoidal ; maxillary and labial palpi simi- 

 lar, the terminal joint largest, longer than wide, moderately dilated 

 outwardly and obliquely truncate in the greater number of species, 

 feebly dilated or nearly parallel in a few — e. g. granulatus and 

 luteipeanis ; widest at or behind the middle, narrowed and feebly 

 truncate at apex in marginicollis, gentilis and trapezoideus. Lab- 

 rum strongly transverse, truncate or broadly arcuate in front. 

 Antenna? 11-jointed, rarely 10 jointed (gentilis and trapezoideus), as 

 long as or a little longer than half the body in the male, somewhat 

 shorter in the female; the three outer joints much elongated and 

 usually wider than the intermediate ones, which are not at all ser- 

 rate. First joint moderately stout, second shorter and narrower but 

 similar; the following joints somewhat variable in their relative 

 lengths, but the third, fifth and seventh usually obviously longer 

 than those adjacent to them, sixth to eighth shorter than those pre- 

 ceding, eighth shortest and sometimes distinctly transverse; ninth 

 to eleventh not very unequal in length, their united length, except 

 in females of a few species, longer than all the preceding and always 

 longer in the male, in which they are narrower and more filiform 

 than in the female. Eyes strongly convex, variable in size, but 

 larger in the male. Epistoma short, the suture usually more or less 

 arcuate and lightly impressed ; straight or sinuate at middle and 

 rather deeply impressed in marginicollis and trapezoideus. Pro- 

 thorax wider than the head, except in male of trapezoideus, trans- 

 verse, sides narrowly or more commonly rather widely margined 

 (not margined in trapezoideus), hind angles sharply defined in 

 trapezoideus only, usually more or less broadly rounded and often 

 completely undefined. 



Elytra parallel, elongate, as wide as or a little wider than the 

 prothorax ; confusedly punctate. Presternum moderate or short 

 before the coxa?, varying from about one fourth the longitudinal 

 diameter of the coxa in granulatus to one-half in marginicollis. 

 Mesosternum moderate in length, oblique, becoming nearly horizon 



TRANS. AM. ENT. SOC. XXXI. APRIL, 1905. 



