The American Naturalist, Volumen30Essex Institute, 1896 |
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Página 18
... adaptations to the circumstances in which the plant lives . It is the effort to adapt itself to circumstances which gives rise to the varia- tion . The whole structure of agriculture is built upon this fact . All the value of tillage ...
... adaptations to the circumstances in which the plant lives . It is the effort to adapt itself to circumstances which gives rise to the varia- tion . The whole structure of agriculture is built upon this fact . All the value of tillage ...
Página 19
that the same kind of adaptations to conditions are proceeding everywhere before our eyes . We cannot stroll afield without seeing it . Dandelions in the hollows , on the hillocks , in the roadside gravel , in the garden - they are all ...
that the same kind of adaptations to conditions are proceeding everywhere before our eyes . We cannot stroll afield without seeing it . Dandelions in the hollows , on the hillocks , in the roadside gravel , in the garden - they are all ...
Página 22
... adaptations which are directly produced by those conditions are without permanent effect . In the fourth place , we know as a matter of common knowledge and also of direct experiment , that acquired characters in plants often are ...
... adaptations which are directly produced by those conditions are without permanent effect . In the fourth place , we know as a matter of common knowledge and also of direct experiment , that acquired characters in plants often are ...
Página 61
... adaptation des plantes au climat alpin . Plants of many genera were removed from the plains , the roots or root - stocks divided into equal parts , and these parts set in similar soil and situations at various ele- vations , up to ...
... adaptation des plantes au climat alpin . Plants of many genera were removed from the plains , the roots or root - stocks divided into equal parts , and these parts set in similar soil and situations at various ele- vations , up to ...
Página 158
... adaptation , that the adaptation of the individual organ is the result of use , and that the effects of use can be inherited . In supporting this position he gave many illustrations , based upon his personal observation . He held ...
... adaptation , that the adaptation of the individual organ is the result of use , and that the effects of use can be inherited . In supporting this position he gave many illustrations , based upon his personal observation . He held ...
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Términos y frases comunes
acid adaptations Amer American animals appear augite bacteria beds beets birds bones Botany Bull cells characters cleavage color containing Cope crystals described diabases Diplopoda disease eggs embryo Eocene evidence evolution experiments Extr fact fauna fishes formation fossil gabbro gastrula gelatine genera genus Geol Geological gneisses heredity hornblende Hyracotherium IIBr insects Journ known Lacertilia larvæ latter length limestone lower mass ment method molars movements Museum mushroom bodies natural NATURALIST North observed occur organism original orthoclase Paleontology paper paroccipital phenocrysts plagioclase plants plates porphyritic premolar present probably Prof Professor protoplasm quartz recent referred region relation rocks Science segment selection skull species specimens spores sporophylls squamosal stage stain stem structure subspecies substance surface tail tion tissues University upper variations vegetative vessels xylem
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Página 331 - KOREAN GAMES: WITH NOTES ON THE CORRESPONDING GAMES OF CHINA AND JAPAN, Stewart Culin.
Página 878 - Its power of inducing fermentation in a solution of sugar was entirely destroyed, although no perceptible change in the appearance of the yeast cells could be detected under the microscope. This experiment was repeated several times, and always with the same result, although when the yeast was simply washed in water it readily induced fermentation.
Página 182 - Consequently, if the theory be true, it is indisputable that before the lowest Cambrian stratum was deposited, long periods elapsed, as long as, or probably far longer than, the whole interval from the Cambrian age to the present day; and that during these vast periods the world swarmed with living creatures.
Página 818 - With this, the priest disappeared. I awoke at once and immediately told my wife the dream that I might not forget it. Next morning — Sunday — I examined the fragments once more in the light of these disclosures, and to my astonishment found all the details of the dream precisely verified in so far as the means of verification were in my hands. The original inscription on the votive cylinder read: "To the god Ninib, son of Bel, his lord, has Kurigalzu, pontifex of Bel, presented this.
Página 827 - Assistant Secretary of the Smithsonian Institution and Director of the National Museum, died in Washington, Sept.
Página 643 - ... 3. They show no intimate association in areal distribution with the blue limestone, nor any tendency to grade into it." " 4. The metamorphic changes to which the white limestones have been subjected are general in their nature, and...
Página 525 - With the opposite (withdrawing, depressive affects) in injurious and painful conditions. ments) — but by the reinstatement of it by a discharge of the energies of the organism, concentrated as far as may be for the excessive stimulation of the organs (muscles, etc.) most nearly fitted by former habit to get this stimulation again (in which the " stimulation " stands for the condition favorable to adaptation).
Página 952 - We must therefore picture to ourselves a fertile plain occupying the whole of the Bristol Channel, and supporting herds of reindeer, horses, and bisons, many elephants and rhinoceroses, and now and then being traversed by a stray hippopotamus, which would afford abundant prey to the lions, bears, and hyaenas, inhabiting all the accessible caves, as well as to their great enemy and destroyer, man."* III.
Página 416 - heightened discharge " are capable of formulation of the principle of " motor excess " : " the accommodation of an organism to a new stimulation is secured — not by the selection of this stimulation beforehand (nor of the necessary movements) — but by the reinstatement of it by a discharge of the energies of the organism, concentrated, as far as may be, for the excessive stimulation of the organs (muscles, etc.), most nearly fitted by former habit to get this stimulation again," '' in which...
Página 495 - ... on the way to Pawtucket; he wanted to get away somewhere — he didn't know where — and have rest. He had six or seven hundred dollars with him when he went into the store. He lived very closely, boarded by himself, and did his own cooking. He went to church, and also to one prayer-meeting. At one of these meetings he spoke about a boy who had kneeled down and prayed in the midst of the passengers on a steamboat from Albany to New York [an incident of which he was well aware in the Ansel Bourne...