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Show FOSSIL COLEOPTERA FROM THE ROCKY MOUNTAIN TERTIARIES. By SAMCEL H. SCUHDER. In this paper are made known the first fossil Ooleoptera 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 Ooleoptera from any formation. Two beetles have been figured by Heer from the Miocene of Northern Greenland, and these are all that have yet been described from the New World. The preliminary descriptions here presented* are published in the hope of drawing attention to the rich deposits of the West, which will doubtless 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 accompjish which the assistance of those who may be able to make collections in the Rocky 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 Ooleoptera and for assistance in other ways. Descriptions of the other groups of insects will follow from time to time. Bembidium exoletum.- A single, rather well- preserved specimen, exhibiting the upper surface and impressions of parts of the legs, was found by Prof. W. Denton ( the first discoverer of Tertiary insects in America) in the Green River group, near White River, in one of the two localities called by him Chagrin Valley and Fossil Canon. It is about the size of Bemb. incequale ( Say). The head is too poorly preserved to present any characters; the pronotum is of equal width anteriorly 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. incequale and are provided with seven or eight very delicately impressed longitudinal striae, made up apparently of a series of adjacent punctures; the sutural edge is delicately marginate. The fragments of legs show simply that they are of the form usual in Bembidium. Length of insect 4.75mm, of pronotum .88mm; width of same in the middle 1.2mm; of same at the posterior border lmm; of the body at the • .- --^/ * For previous general accounts of the collections of Professor Denton and Mr. Richardson, upon which the following descriptions are principally based, see: Proc. Boat.- * » c. Nat. Hist., x, 305,6; xi, 117- rf. Amer. Nat., i, 56; vi, 665- 8. Geol. Mag., v, 220- 2 HolVmter, Mines of Colorado, 378- 87. |