U.S. Geological Survey Professional Paper

Front Cover
U.S. Government Printing Office, 1937 - Geology
 

What people are saying - Write a review

We haven't found any reviews in the usual places.

Other editions - View all

Common terms and phrases

Popular passages

Page 19 - Very gradually the tropical members of the flora disappeared ; that is to say, they migrated, formest of their types, I think, actually survive at the present day, many but very slightly altered. Then the sub-tropical members decreased, and the temperate forms, never quite absent even in the middle eocenes, preponderated. As decreasing temperature drove the tropical forms south, the more northern must have pressed closely upon them. The northern eocene, or the temperate floras of that period, must...
Page 27 - Test ellipsoidal or ovoid to cylindrical, rounded at the base, slightly produced at the apertural end ; chambers rounded almost as long as broad, arranged in a nearly triserial series, each succeeding chamber removed much farther from the base, rarely becoming almost uniserial in the last chamber; sutures but little depressed, generally distinct; wall smooth, thick, often with fistulose tubes; aperture radiate. Length 0.60 mm.
Page 38 - ... triangular in cross section, early portion tapering, adult portion with the sides nearly parallel and straight : chambers numerous, arranged triserially ; sutures not depressed, often slightly limbate; sides of the test flattened or very slightly concave; peripheral angles rounded; aperture slightly elongate at the base of the inner margin of the last-formed chamber ; wall finely punctate. Length 1 millimeter or less.
Page 49 - ... at the inner margin of the last-formed chamber on the ventral side, covered with a thin lip, wall smooth, slightly perforate.
Page 26 - Geology and mineral resources of Iron Creek, by PS Smith. In Bulletin 314, 1907, pp. 157-163. The gold placers of parts of Seward Peninsula, Alaska, including the Nome, Council, Kougarok, Port Clarence, and Goodhope precincts, by AJ Collier, FL Hess, PS Smith, and AH Brooks. Bulletin 328, 1908, 343 pp. 'Investigation of the mineral deposits of Seward Peninsula, by PS Smith. In Bulletin 345, 1908, pp.
Page 26 - Pliocene and Pleistocene Fossils from the Arctic Coast of Alaska and the Auriferous Beaches of Nome, Norton Sound, Alaska.
Page 40 - ... ornamented with longitudinal costae in the earlier portion, the costae not confluent with those chambers above or below, costae later tending to break up into lines of spines, and the later portion of the test in adults generally hispid, about twenty costae in the complete circumference before the breaking into spines; apertural end with a slightly tapering subcylindrical neck and slight phialine lip.
Page 9 - Kemp, JF, The ore deposits of the United States and Canada, 3d ed., p.
Page 5 - Charles W. Eliot and Frank H. Storer. On the Impurities of Commercial Zinc, with special Reference to the Residue insoluble in Dilute Acids, to Sulphur, and to Arsenic.
Page 26 - A geologic reconnaissance in southeastern Seward Peninsula and the Norton BayNulato region, by PS Smith and HM Eakin.

Bibliographic information