FOSSIL COLEOPTERA FROM THE ROCKY MOUNTAIN TERTIARIES. 



By Samuel H. Scudder. 



lu this paper are made known the first fossil Coleoptera from the 

 Tertiaries of the United States ; indeed, if we except some doubtful 

 remains found in the red sandstone of the Connecticut Valley, the first 

 distinctively American Coleoptera from any formation. Two beetles 

 have been figured by Heer from the Miocene of jSTorthern Greenland, 

 and these are all that have yet been described from the New World. 

 The preliminary descriptions here presented* are jDublished in the hope 

 of drawing attention to the rich deposits of the West, which will doubt- 

 less prove as fertile as those of Europe. Most of the species have 

 already been drawn for plates which I hope soon to publish in a general 

 work on the fossil insects of the American Tertiaries, to accomplish which 

 the assistance of those who may be able to make collections in the 

 Eocky Mountain region is earnestly solicited. 



In the determination of the generic affinities of these insects I have 

 been greatly assisted by the kind advice of my esteemed friend Dr. J. 

 L. LeConte, although he is in no way to be held responsible for any 

 errors I may have committed in studying a group of insects less familiar 

 to me than are others. I am also indebted to Mr. E. P. Austin for the 

 use of his rich collection of American Coleoptera and for assistance in 

 other ways. 



Descriptions of the other groups of insects will follow from time to 

 time. 



Bemhidium exoJetum. — A single, rather well-preserved specimen, ex- 

 hibiting the upper snrface and impressions of parts of the legs, was 

 found by Prof. W. Denton (the first discoverer of Tertiary insects 

 in America) in the Green Eiver gronp, near White Elver, in one of the 

 two localities called by him Chagrin Valley and Fossil Caiiou. It is 

 about the size of Bemb. imcquale (Say). The head is too poorly pre- 

 served to present any characters ; the pronotum is of equal width an- 

 teriorly and posteriorly, its sides regularly and considerably convex, 

 the posterior angles well defined, the hind margin slightly convex ; its 

 surface appears to be very faintly punctulate, at least posteriorly, and 

 there is a slightly impressed median line. The elytra are shaped as in 

 B. imvqiiale and are provided with seven or eight very delicately im- 

 pressed longitudinal strine, made up apparently of a series of adjacent 

 punctures; the sutural edge is delicately marginate. The fragments of 

 legs show simi)ly that they are of the form usual in Bembidium. 



Length of insect 4.75""", of pronotum .88'""'; width of same in the mid- 

 dle 1.2'"'"; of same at the posterior border 1"""'; of the body at the 



*For previous general accounts of the collections of Professor Denton and Mr. Rich- 

 ardson, upon which the following descriptions are principally based, see: Proc. Bost.- 

 Soc. Nat. Hist., s, 1305, G ; xi, 117-8. Amer. Xat., i, oC ; vi, 665-?. Geoi. Mag., v, '^t-O-g 

 Hollister, Mines of Colorado, o78-t;7. 



