176 GEO. H. HORN, M. D. 



always decidedly longer than the third. Tarsi slender in both sexes, 

 the anterior slightly dilated in the male and with two or three joints 

 spongy pubescent beneath. 



In this genus the elytra are either striate or striato-punctate, the 

 inflexed portion either smooth or obsoletely punctate, the apex usually 

 gradually declivous. The palpi of the male have a broader terminal 

 joint than those of the female, and the tarsi slightly dilated with a 

 variable number of joints pubescent. 



This genus is composed of species peculiar to the true Pacific Coast 

 fauna of North America, which extends from Alaska to San Diego, 

 and is limited on the east by the snow-clad Sierras of California and 

 their extension northward to Alaska. 



The species are again capable of subdivision on characters not 

 sexual, as follows : 



Head cristate to a greater or less extent, gula deeply transversely impressed. 

 Three joints of anterior tarsi % pubescent beneath. 

 Basal joint of auteunse very stout and longer than the third, gense deeply 



incised Group I. 



Head feebly convex, gula not transversely impressed, genae more or less 

 incised. 

 Basal joint of antennae normally slender , , Group II. 



Group I. 



Head cristate, gula deeply transversely impressed, antennae slender, 

 basal joint much stouter than normal, genje beneath the eyes incised. 

 x\nterior tarsi with three dilated joints, which are spongy pubescent 

 beneath, fourth joint without brush of hairs. 



Two species occur in our fauna. 



Front strongly cristate, occiput deeply transversely impressed, basal impression 

 of thorax deep. Elytra with rows of moderate punctures which are often 

 more or less confused erisfatus. 



Front feebly obtusely carinate, occiput not impressed, basal impression of 

 thorax feeble. Elytra striate, striae distantly punctured rilgiceps. 



C cristatus Harris, Bost. Journ. ii, p. 200 ; reticulaius Mots. Kafer Russ. 

 p. 90 ; Mann. Bull. Mosc. 1862, ii, p. 292 ; 1853, iii, p. 121.— Moderately elongate, 

 black, shining. Head moderately elongate, vertex cristate, crest irregular at 

 summit in front, suddenly declivous posteriorly by a deep occipital impression, 

 supra-orbital ridges strongly elevated, genae dilated and beneath the eyes very 

 deeply incised so as to appear bilobed, surface impunctured. Antennae slender, 

 the basal joint large and stout. Thorax cordate, posteriorly constricted, hind 

 angles rectangular, sides in front arcuate, disc moderately convex, anterior 

 and posterior impressions deep, the median less impressed, apical bead pos- 

 terior to the apical margin, side margin with a moderately thickened bead, 

 surface smooth. Elytra oval, convex, margin very narrow, surface faintly 



