The Shipley Collection of Scientific Papers, Volumen231897 |
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Página 12
... differentiation in cleavage has been going forward , through which the posterior cell of this quartet has become more and more strictly given over to the formation of mesoblast . The vestigial cells of Aricia , Spio , Amphitrite and ...
... differentiation in cleavage has been going forward , through which the posterior cell of this quartet has become more and more strictly given over to the formation of mesoblast . The vestigial cells of Aricia , Spio , Amphitrite and ...
Página 26
... differentiation - process ; and it would be difficult to explain such ancestral reminiscence in cell- lineage under any view which does not recognize in cell - out- lines the definite boundaries of differentiation - areas in the de ...
... differentiation - process ; and it would be difficult to explain such ancestral reminiscence in cell- lineage under any view which does not recognize in cell - out- lines the definite boundaries of differentiation - areas in the de ...
Página 73
... differentiation . Pfeffer's definition differs still more widely from mine . He defines growth as change in form in the protoplasmic body ( " die gestaltliche Aenderung im Protoplasmakörper " ) , and he goes on to say that increments of ...
... differentiation . Pfeffer's definition differs still more widely from mine . He defines growth as change in form in the protoplasmic body ( " die gestaltliche Aenderung im Protoplasmakörper " ) , and he goes on to say that increments of ...
Página 74
... differentiation alone , and , finally , of increase of volume alone . Returning now to the definition proposed above , we see that growth as mere increase of volume is to be distinguished from development , from differentiation , even ...
... differentiation alone , and , finally , of increase of volume alone . Returning now to the definition proposed above , we see that growth as mere increase of volume is to be distinguished from development , from differentiation , even ...
Página 77
... comes the period of histological differentiation and deposition of formed . substance , during which the amount of dry substance increases enormously , so that the percentage of water falls to DAVENPORT : THE ROLE OF WATER IN GROWTH . 77.
... comes the period of histological differentiation and deposition of formed . substance , during which the amount of dry substance increases enormously , so that the percentage of water falls to DAVENPORT : THE ROLE OF WATER IN GROWTH . 77.
Términos y frases comunes
American eggs Amphioxus animals annelids appear Appendicularia archenteron Aricia arrangement autotomy axis-cylinder process bones buds cave-earth cavern cell body cell of Helix cell-lineage cells of Invertebrates cellular centrosomes character chromophilous chromophilous granules chromosomes colonial condition curve density depth determined differentiation direction disease distilled water division ecdysis embryo entoblastic evidence existence fact fathoms fibrils FLEMMING'S foliage-leaves function ganglion cells gasteropods geological germ-plasm give granular rows ground-substance growth haematoxylin Heredity hydrometer individual investigation large number latter leaves Leptoplana mesoblast-bands mesoblasts metamorphosis method methylen blue morphological Museum naturalists Nereis nerve cells neuroglia neuroglia fibrils nucleus observations ocean offspring organs origin plant plate polyclade position posterior present primary mesoblasts produce quartet regard reproductive cells safranin segmentation segmentation nucleus slug solution species specimens spindles spiral sporophyll stained stalagmite stem structure substance surface tarsus temperature theory tion tissues variations Vertebrates
Pasajes populares
Página 7 - I happened to read for amusement 'Malthus on Population', and being well prepared to appreciate the struggle for existence which everywhere goes on from long-continued observation of the habits of animals and plants, it at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed. The result of this would be the formation of new species. Here then I had at last got a theory by which to work...
Página 2 - And pretty dwarfs to show the way Through fairy hills and fairy dales. But when a bad child goes to bed, From left to right she weaves her rings, And then it dreams all through the night Of only ugly horrid things ! Then lions come with glaring eyes, And tigers growl, a dreadful noise, And ogres draw their cruel knives, To shed the blood of girls and boys.
Página 2 - LITTLE fairy comes at night, Her eyes are blue, her hair is brown, With silver spots upon her wings, And from the moon she flutters down. She has a little silver wand, And when a good child goes to bed She waves her wand from right to left, And makes a circle round its head.
Página 11 - human remains and works of art, such as arrow-heads and knives of flint, occur in all parts of the cave and throughout the entire thickness of the clay : and no distinction founded on condition, distribution, or relative position, can be observed, whereby the human can be separated from the •other reliquiae," which included bones of the "elephant, rhinoceros, ox, deer, horse, bear, hyaena, and a feline animal of large size.
Página 4 - Les noms géographiques des nations qui emploient, dans leur écriture, des caractères latins (langues néo-latines, germaniques, Scandinaves), seront écrits avec l'orthographe de leur pays d'origine. Les règles qui vont suivre s'appliquent uniquement aux noms géographiques de pays qui n'ont point d'écriture propre ou qui écrivent avec des caractères différents des caractères latins. Toutefois, à titre exceptionnel, on conservera l'orthographe usitée pour les noms de lieux, lorsqu'elle...
Página 8 - It may well be doubted ; and yet one is always the better for a walk in the morning air, — a medicine which may be taken over and over again without any sense of sameness, or any failure of its invigorating quality.
Página 12 - Whatever other causes have been at work, natural selection is supreme, to an extent which even Darwin himself hesitated to claim for it. The more we study it the more we are convinced of its overpowering importance, and the more confidently we claim, in Darwin's own words, that it ' has been the most important, but not the exclusive, means of modification...