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acid America appears base beds belong called Cambrian Canada Carboniferous character classification Coal Measures conglomerate considered containing correlation County deposits described determined Devonian district division eastern equivalent evidence extending fact fauna feet field formation forms fossils Geol geological Geological Survey geologists given gray Hall horizon included indicated John Jour known Lake latter layers limestone localities Lower Michigan Middle mineral Mountain North northern notes observed occur Ohio organic Paleozoic Pennsylvania Permian portion position Potsdam sandstone present Primordial probably Prof Province published quartz quartzite range recognized referred regarded region relations remains represented resting River rocks sand separated shales side Silurian slates species stone strata stratigraphic Survey thickness tion Upper Valley Vermont western Wisconsin York zone
Page 9 - NICHOLSON. A Manual of Zoology, for the use of Students. With a General Introduction on the Principles of Zoology. By HENRY ALLEYNE NICHOLSON, MD, D.Sc., FLS, FGS, Regius Professor of Natural History in the University of Aberdeen.
Page 61 - NOTE. — In addition to the evidence heretofore possessed regarding the position of the shales containing the Trilobites, I have the testimony of Sir WE Logan, that the shales of this locality are in the upper part of the Hudson River group, or forming a part of a series of strata which he is inclined to rank as a distinct group, above the Hudson River proper. It would be quite superfluous for me to add one word in support of the opinion of the...
Page 177 - Descriptions of new organic remains collected in Nebraska Territory in the year 1857, by Dr. FV Hayden, geologist to the exploring expedition under the command of Lieut. GK Warren, Top. Engr. US Army, together with some remarks on the geology of the Black Hills and portions of the surrounding country.
Page 96 - A reprint of the annual reports and other papers on the geology of the Virginias.
Page 95 - These markings are of a flattened, cylindrical form, from ith to -,'jth of an inch broad, giving the surface of the fractured rock a ribbed appearance, and resembling perforations made in sand which have been subsequently filled up, without destroying the distinctness of the original impression.
Page 364 - He here advanced the idea that the enumeration of the mineral constituents of rocks could never be satisfactorily applied for the determination of the relative position of strata, but that recourse must be had to the organic remains. " We find the same organized remains associated with equivalent strata in every part of the earth...
Page 98 - On the map accompanying the paper (p. 170), an ideal section shows the shales and conglomerates resting on the gneiss beneath the sandstone, which they have referred to the Potsdam owing to its carrying Scolithus borings, and above the latter is the slate belt, in which the quarries are located. Under the title of " Geology of the Blue Ridge near Balcony Falls, Virginia ; a modified view,
Page 167 - ... siliceous sandstone. In many places, this most ancient of the fossiliferous rocks of New York (the Potsdam sandstone) is divided into laminae by the remains of innumerable shells of the genus Lingula. They are in such profusion as to form black seams like mica, for which they were at first mistaken.* With the Lingula occurs another small placunoid shell, allied to, if not identical, according to Professor E.