AMERICAN COLKOPTKRA. 187 



2. Hind angles of p rot ho rax clothed above and beneath with dense yellow hair. 



2. americanus. 



Hind angles of thorax without patch of yellow hair 3. 



3. First joint of antennal club equal to three preceding; disk of thorax distinctly 



longitudinally impressed, apex of elytra scarcely truncate. 



Vestiture of elytra very short, inconspicuous and almost perfectly recum- 

 bent, the alternate interspaces not elevated 3. quadrulns. 



Vestiture of elytra more conspicuous and with numerous more prominent 

 short recurved hairs; alternate interspaces slightly more convex and 



more pubescent 4. alternatus. 



First joint of antennal club equal to the two preceding; disk of prothorax not 

 distinctly longitudinally impressed ; apex of elytra truncato-emargi- 

 nate 5. truncatus. 



1. C. not at u«* Say. — Moderately elongate, suhcylindrical, dark brown. Ves- 

 titure short, recumbent, dark brown, variegated with yellowish cinereous as fol- 

 lows: the base, median channel and two small discal spots on the prothorax ; and 

 on the elytra, basal, submedian and posterior transverse fasciae, which are quite 

 irregular, being usually more or less broken up into elongate spots. Head 

 sparsely granulate ; ninth antennal joint equal to or a little longer than the three 

 preceding. Prothorax as wide as the elytra, sides parallel in basal two-thirds, 

 distinctly sinuate before the hind angles, which are right or slightly acute; disk 

 channeled from the front margin to the posterior depression ; surface deeply con- 

 cave within the angles. Elytra with closely punctate stria-, the intervals not 

 wider than the strise. Mesosternum and abdomen moderately closely, coarsely 

 annulate or lunate-punctate. Length 3.2-4 mm. 



New England States and Canada to Michigan, Missouri and 

 North Carolina. This is our prettiest species and the only one 

 occurring in the Eastern States. It is said in the Washington 

 List to occur on old oak branches. 



2. C americanus n. sp. — Oblong, robust, piceous-brown, not shining, pu- 

 bescence fine, short, and perfectly appressed. Head moderately closely granu- 

 late, ninth antennal joint but little wider than the preceding and a little shorter 

 than the next three. Prothorax as wide as the elytra at base, sides nearly par- 

 allel, not sinuate before the hind angles which are a little, obtuse. Disk distinctly 

 impressed at middle, transversely impressed along the base each side, the impres- 

 sion becoming deeper toward the angles, the latter with a dense patch of ap- 

 pressed yellow hair which is continued beneath along the hind margin of the 

 flanks and also on the contiguous surface of the humeri and on the mesosternal 

 side pieces. Elytral strife distinctly impressed, the interspaces, except near the 

 suture not or scarcely wider than the strise and distinctly convex. Metasternum 

 strongly grauulato-tuberculate ; ventral segments with the usual annular punct- 

 uation which tends strongly to become tuberculate toward the sides; last ventral 

 concave before the apex, the apical margin deflexed. Length 4.5-5.5 mm. 



Colorado (Ouray and Silver Plume, Wickham) ; National Park, 

 Wyoming (Schwarz). 



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



