Proceedings of the American Association for the Advancement of Science, Količina 26 |
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Pogosti izrazi in povedi
aberration abundant acid Actinopteri adopted Agassiz alloys American Amia ancient animals argillitic Association beds bones Boston Buffalo Cambridge character Cincinnati College Conn continued Cretaceous deposits depth determined diorite east engine Eocene existing extinct F. W. Putnam feet fishes formation fossil genera genus Geological gneiss Gulf heat Hudson inches Indians indicate James John Kennebago lake Kennebago river known latter limestone Linnæus mammals Mass meeting miles Miocene Mississippi Nashville naturalists nearly nomenclature Obeys river Ohio paper Pass Permanent Secretary Philadelphia Pliocene precipitates present President probably Prof region remains represented river rocks sandstone schist scientific shales South species specific name specimens spherical aberration Standing Committee staurolite strata stream strontium strontium chloride surface Survey synonymy teeth Tenn Tertiary tion tribes Ungulates valley vertebrates Washington William York
Priljubljeni odlomki
Stran 386 - Gardiner's rivers; thence east to the place of beginning is hereby reserved and withdrawn from settlement, occupancy, or sale under the laws of the United States and dedicated and set apart as a public park or pleasuring ground for the benefit and enjoyment of the people...
Stran xxiv - All money thus received shall be invested as a permanent fund, the income of which shall be used only to assist in original research, unless otherwise directed by unanimous vote of the Standing Committee.
Stran 230 - ... better ; and that vertebrates afford the most reliable evidence of climatic and other geological changes. The subdivisions of the latter group, moreover, and in fact all forms of animal life, are of value in this respect, mainly according to the perfection of their organization, or zoological rank. Fishes, for example, are but slightly affected by changes that would destroy Reptiles or Birds, and the higher Mammals succumb under influences that the lower forms pass through iu safety. The more...
Stran xvii - The objects of the Association are, by periodical and migratory meetings, to promote intercourse between those who are cultivating science in different parts of...
Stran 98 - ... and to prepare tables which will exhibit the strength and value of said materials for constructive and mechanical purposes, and to provide for the building of a suitable machine for establishing such tests.
Stran 92 - If this axiom be denied for all temperatures, it would have to be admitted that a self-acting machine might be set to work and produce mechanical effect by cooling the sea or earth, with no limit but the total loss of heat from the earth and sea, or, in reality, from the whole material world.
Stran 237 - Pliohippus, which has lost the small hooflets, and in other respects is very equine. Only in the Upper Pliocene does the true Equus appear and complete the genealogy of the horse, which in the Post-Tertiary roamed over the whole of North and South America, and soon after became extinct.
Stran 228 - ... therefore, was that birds sprang from some primitive and unknown type of dinosaur. The conception of direct descent of birds from dinosaurs gained ground until it reached the force of positive theory in the writings of Hoernes, and especially of Marsh, as seen in the following paragraph ('77, p. 228) : " It is now generally admitted by biologists who have made a study of the vertebrates that birds have come down to us through the dinosaurs, and the close affinity of the latter with recent struthious...
Stran 236 - The oldest representative of the horse, at present known, is the diminutive Eohippus from the lower Eocene. Several species have been found, all about the size of a fox. Like most of the early mammals, these Ungulates had forty-four teeth, the molars with short crowns, and quite distinct in form from the premolars. The ulna and the fibula were entire and distinct, and there were four well developed toes and a rudiment of another on the fore feet, and three toes behind.
Stran 236 - Eohippus, and showing a greater, although still distant, resemblance to the Equine type. The rudimentary first digit of the fore-foot has disappeared, and the last premolar has gone over to the molar series. Orohippus was but little larger than Eohippus, and in most other respects very similar.