Palæontology, Band 1

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Caxton Press of Sherman & Company, 1864 - 299 Seiten
 

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Seite xvii - Pluroas county, California. But sufficient paleontological evidence has been obtained to enable us to state that this formation extends from Mexico to British Columbia, occupying a vast area, although much broken up, interrupted, and covered by volcanic and eruptive rocks, and usually highly metamorphosed. Among the specimens from the Humboldt and Flumas county, Mr.
Seite 107 - Cal., vol. 1, p. 109, pi. 21, fig. 112, 1864. Shell medium-size, auriform; spire slightly prominent, whorls four, rapidly increasing in size ; suture faintly canaliculate; surface marked by numerous compound revolving lines, minutely waved laterally and showing a tendency to an alternation of larger and smaller ones ; these are crossed by irregular lines of growth, which completely encircle the whorls, and are most distinct and crowded in the umbilicus; aperture patulous, acute behind ; inner lip...
Seite xviii - America is chiefly made up of rocks of Jurassic and Triassic age, with a. comparatively small development of Carboniferous limestone, and that these two formations are so folded together, broken up, and metamorphosed in the great chain of the Sierra Nevada, that it will be an immense labor, if indeed possible at all, to unravel its detailed structure. While we are fully justified in saying that a large portion of the auriferous rocks of California consist of metamorphic...
Seite iii - California ; JD WHITNEY, State Geologist. — PALEONTOLOGY, Volume I: Carboniferous and Jurassic fossils, by F. B. MEEK; Triassic and Cretaceous Fossils, by WM GABB.
Seite xvii - Perhaps the most striking result of the survey is the proof we have obtained of the immense development of rocks, equivalent in age to the upper Trias of the Alps, and paleontologically closely allied to the limestones of Hallstadt and Aussee, and the St. Cassian beds, that extremely important and highly fossilliferous division of the Alpine Trias.
Seite viii - He shall be commissioned by the Governor, and it shall be his duty, with the aid of such assistants as he may appoint, to complete the Geological Survey of the State, and prepare a Report of said Survey for publication, and superintend the publication of the same. Such Report shall be in the form of a geological, botanical, and zoological history of the State...
Seite 211 - Kept, pt. 1, p. 1044, pi. 66, fig. 3. "Shell elongated, tapering, scaliform; whorls numerous, sloping, straight, or somewhat concavely outwards above, angulated and obliquely truncated below" ; suture impressed and carinated by a small tubercular spiral rib. "Surface marked by numerous fine, revolving thread-like lines, sometimes alternating in size, and on the angle near the lower margin of the whorl, by coarse granulations. Aperture subquadrate.
Seite xviii - ... particle of evidence to sustain the theory which has been so often brought forward, that all, or even a portion of the auriferous rocks are older than the Carboniferous, not a trace of a Devonian or Silurian fossil ever having been discovered in California. or indeed any where to the west of the n6th meridian. It appears, on the other hand, that no inconsiderable amount of gold has been obtained from metamorphic rocks, belonging as high up in the series as the Cretaceous.* While such are the...
Seite 186 - ... Figure 4 Trigonia tryoniana Gabb, Pal. Cal. Vol. 1, p. 188, pi. 25, fig. 176, 1863. Whiteaves Mesozoic Fossils, Vol. 1, p. 161, pi. 18, fig. 7, 1876. Gabb originally described this species as follows : Shell elongate, subquadrate, narrowest behind; beaks anterior, not prominent, subterminal; hinge line straight, obliquely sloping; anterior end rounded, base convex in front, straight and sloping upwards behind, posterior end convexly subtruncated. Surface marked by two radiating grooves, one of...
Seite xviii - California, or indeed anywhere to the west of the 116th meridian. On the Other hand, we are able to state, referring to the theory of the occurrence of gold being chiefly limited to Silurian rocks, that this metal occurs in no inconsiderable quantity in metamorphic rocks belonging as high up in the series ae the cretaceous.

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