NORTH AMERICAN COLEOPTERA. 259 



long and dense % , very short 9 • Abdomen sparsely, rather finely punctate at 

 the sides, the last two segments more coarsely. Claws curved, the tooth strong 

 and median. Last joint of maxillary palpus moderately elongate, slightly fusi- 

 form, not impressed. Length .70 —.90 inch ; 18 — 23 mm. 



Male. — Antennal club ii little longer than the stem. Abdomen 

 flattened at middle, penultimate segment deeply transversely de- 

 pi-essed in its posterior half, on each side of which is a feeble obtuse, 

 obliijue elevation. Last segment concave, smooth, the apex broadly 

 triangularly emarginate closed by membrane. Inner spur of hind 

 tibia half the length of the outer, acute at tip. 



Female. — Antennal club small and lenticular, shorter than the 

 funiculus. Penultimate ventral segment with a linear transverse 

 impression near the posterior border, the last segment broadly emar- 

 ginate. Posterior tarsi slightly shorter than the male. 



Variations. — The usual vai-iation in color from rufocastaneous 

 to brown exists in this species, the latter color seeming to prevail in 

 the Avestern specimens (Nebraska). The angulation of the thorax 

 varies in a marked degree, and some of the specimens approach 

 affinis in such a decided manner that they might be placed together 

 without reference to other characters ; corrosa is also -closely related 

 in form and the sexual characters of the male alone separate them 

 with certainty. The extent of the emargination of the last ventral 

 segment ? varies in extent from a deep, squarely cut form to an 

 arcuate emargination. 



Occurs from Massachusetts to Colorado southward to North Caro- 

 lina and Texas. 



Group X, balia. 



This group contains a small number of species which have the 

 following characters in common : Inner spur of hind tibia % fixed, 

 and at least half as long as the outer spur. The antennje are 

 9-)ointed. Clypeus emarginate in all the species, although very 

 feebly in comans, in which there is a mere sinuation. The hist joint 

 of the maxillary palpus is fusiform or subcylindrical, not imjiressed. 

 The claws are strongly toothed in all except comans. 



The antennae have been shown to exhibit some variation in the 

 number of joints in other parts of the series, and it might naturally 

 be suspected that the species in the present group are composed of 

 merely aberrant individuals of those series in which the antennie are 

 normally 10-jointed. 



