Proceedings of the Academy of Natural Sciences of PhiladelphiaAcademy of Natural Sciences of Philadelphia, 1885 |
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Abth Acad Academy Alaska American species Anacanthini anal fins animal Annali delle Author Bartlett Bay Bean Bleeker body Bonaparte brain Bulletin Cape San Lucas caudal cells Coast collection color commissure Cuba Cuvier Cuvier & Valenciennes dorsal fin Editor elongated Enum epiphysial feet fibres Florida fossils Gadida Gasterosteus genus Geological Gill gray Günther head Heilprin Hemirhamphus Hist hornblende I. V. Williamson Fund inches Jordan & Gilbert Jordan and Gilbert Key West Lacépède layer Leidy length limestone Linnæus lobe lower Mazatlan Menopoma Museum optic pectorals persons present Phila Pisc plants Poey Poiss portion posterior Proc Prof Professor rays rocks sand schist Sciences Section shells side snout Society specimens spicules sponges statoblasts Stromateus surface Synodus Synonyms synonymy Teuthis THOMAS MEEHAN Trachynotus U. S. Fish U. S. Nat upper Valenciennes ventrals Verein Vertebr
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Stran 302 - IF IT could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down.
Stran 302 - TO SUPPOSE that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest degree.
Stran 366 - Memoranda of the origin, plan and results of the field and other experiments conducted on the farm and in the laboratory of, 1884.
Stran 361 - On the contents of a bone cave in the island of Anguilla (West Indies), 27 pp., 1883 (Smithsonian Contributions, no.
Stran 332 - Washington in every block, cause constant wear and tear to both horse and vehicle ; it is to be hoped that at no very distant day the drainage of the entire city will be underground, and that a more even surface for driving may be obtained. The streets of a city are public property , in which all citizens are more or less interested, and in point of necessity no other public work can equal them ; why, then, is not more attention...
Stran 302 - Yet reason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if any variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection,...
Stran 373 - List of the Vertebrated Animals now or lately living in the Gardens of the Zoological Society of London, 1872 Ditto.
Stran 18 - Clathrulina becomes filled with minute green particles, which, even before liberation, exhibit active motion. A number of these are expelled, enclosed in a thin protoplasmic film or globular sac, which bursts shortly, and the liberated germs swim away. The development of these germs, after this point, is yet to be followed. The fourth mode is still more remarkable, and is also significant in bringing to light a new phase in the life-history of the Heliozoa. The Clathrulina in which these phenomena...
Stran 22 - feebly annulated," presumably from the adherence of effete particles, and their compression by the repeated withdrawal of the ciliated tentacles into the mouth of the tube. This method of prolongation must continue during the residence of the worm, and in consequence, if supported, it may sometimes reach a length which is several times that of its inhabitant.
Stran 326 - Act of the General Assembly of the Commonwealth of Pennsylvania, entitled "An Act to provide for the incorporation and Regulation of certain corporations...