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Academy Amer American Jurassic areas argillaceous Arundel Atlantosaurus Atlantosaurus beds audio frequency audion Black Hills bones brown Bull calcareous Camptosaurus Canon City Canyon character Charles coarse color Colorado Cope Creek cross-bedded Dakota Darton deposition diabase dinosaur discussed east eastern erosion fauna feet thick formation near Canon forms fossils geog Geology George gray sandstone Green clay grid circuit grid condenser hystricomorph Inch invertebrate Isolobodon Journ Jurassic Mammals known Kootenie layers limestone locality maps maroon Marsh McElmo Mexico miles molars Morosaurus Morrison formation oscillations outcrops peneplain Ph.D Plata Plate portion Porto Rico probably Prof program was presented quadrangle quarry Red Beds region River rocks sandstone Sauropoda Secretary SECTION OF BIOLOGY Section then adjourned sediments shale skeleton skull species Stegosaurus stratigraphic Surv telephone thin Tinodon tion U. S. Geol upper valley variegated vertebrate Wealden white sandstone wing circuit wing current Wyoming
Page 90 - Osteology of Haplocanthosaurus, with description of a new species, and remarks on the probable habits of the Sauropoda and the age and origin of the Atlantosaurus beds.
Page 137 - W. — 1909. Osteology of the Jurassic reptile Camptosaurus, with a revision of the species of the genus, and descriptions of two new species.
Page 111 - ... clays with the horizontal banding and frequent nodular ledges also correspond closely to the clays comprising the Oreodon Beds of the White River. Let us attempt to trace the history of the Jurassic formation as evidenced by the nature of the rocks, the stratigraphy and the occurrence of fossils: Given an arm of the Jurassic sea, fed by rivers and open to the ebb and flow of tide waters. Under these conditions the sediments washed down by the river everywhere accumulated slowly, and alternating...
Page 105 - Geratodus only are known, and inasmuch as this genus is supposed to range from the Trias to the present time, these species have no correlating value whatever. "To sum up: there is no valid vertebrate evidence pointing to an age greater than the Purbeck for the Atlantosaurus beds, and but very little for a greater age than that of the Wealden.
Page 103 - Jlypsiloplwdon. again a Wealden type, and the crocodile, Goniopholis, is reported from the Wealden and its marine equivalent, the Purbeckian, not from the older Jurassic levels. "The weight of this evidence would seem to place this fauna beyond the Jurassic into the beginning of Cretaceous times.
Page 199 - Cl is charged in the usual way, but accumulates a charge which is proportional, not to the original signal strength, but to the final amplitude of the oscillations in the grid circuit. The result is a current in the telephone much greater than would have been obtained from the original oscillations in the circuit.
Page 105 - Marsh) is not at all decisive. If the species is correctly referred to Compsemys, all its related forms are of Cretaceous age. Nor is there any evidence to be obtained from the pterosaurs or birds. Of the mammals I will not venture to speak, save that I think that there are too few forms known from the Wealden to offer 1 American Journal oj Science, November, 1895, p.
Page 103 - Titanosaurus is referred by Lydekker to probable Upper Greensand. Remains of the Sauropoda are spoken of as "frequent" in the Wealden, while from the Middle Jura only a few are known, and all these are of one, or at most two, species. I certainly cannot see what evidence these forms present that would lead one to say that the American forms are clearly Jurassic. The range of this suborder, so far as is known, is from the Middle Jurassic to the Upper Cretaceous, though there may be doubt as to the...