The Shipley Collection of Scientific Papers, Volumen231897 |
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Resultados 1-5 de 55
Página 883
... methods which it is the function of a Biological Laboratory to suggest , adopt , and execute . The principle of " Panmixia , " or the " suspension of the pre- serving influence of natural selection , " has formed an integral part of the ...
... methods which it is the function of a Biological Laboratory to suggest , adopt , and execute . The principle of " Panmixia , " or the " suspension of the pre- serving influence of natural selection , " has formed an integral part of the ...
Página 890
... method , I finally adopted the following : Having placed upon each American egg a secret mark , the eggs of both countries were thoroughly mixed together in a single tray . A disinterested person was then requested to select , from the ...
... method , I finally adopted the following : Having placed upon each American egg a secret mark , the eggs of both countries were thoroughly mixed together in a single tray . A disinterested person was then requested to select , from the ...
Página 911
... methods of injury and stimulation caused autotomy after a shorter or longer latent period , demonstrated that the event is dependent on the integrity of the third pair of thoracic ganglia , and is as truly a reflex action as the ...
... methods of injury and stimulation caused autotomy after a shorter or longer latent period , demonstrated that the event is dependent on the integrity of the third pair of thoracic ganglia , and is as truly a reflex action as the ...
Página 914
... method that the capsules obtained later were left undisturbed , as nearly as possible in the exact spots where they had been deposited . But from the whole number of capsules observed , only 20 hatchings were obtained , the total number ...
... method that the capsules obtained later were left undisturbed , as nearly as possible in the exact spots where they had been deposited . But from the whole number of capsules observed , only 20 hatchings were obtained , the total number ...
Página 27
... method of interpretation . In my first paper ( '95 ) I took some pains to make clear the assertion that in the spi- reme stage of the spermatocytes of the first order 24 chromosomes arise . WILSON's statement that " Each of these ...
... method of interpretation . In my first paper ( '95 ) I took some pains to make clear the assertion that in the spi- reme stage of the spermatocytes of the first order 24 chromosomes arise . WILSON's statement that " Each of these ...
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...