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Página 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 America, to give a stronger and more general impulse and more systematic direction to scientific research, and to procure for the labors of scientific men increased facilities and a wider usefulness.
Página 182 - ... gemmules. They are supposed to be transmitted from the parents to the offspring, and are generally developed in the generation which immediately succeeds, but are often transmitted in a dormant state during many generations and are then developed. Their development is supposed to depend on their union with other partially developed cells or gemmules which precede them in the regular course of growth.
Página 252 - Running fires are set everywhere, with a view to clearing the ground of prostrate trunks, to facilitate the movements of the flocks and improve the pastures. The entire forest belt is thus swept and devastated from one extremity of the range to the other, and, with the exception of the resinous Pinus contorta, sequoia suffers most of all.
Página 171 - He is plantigrade, has five toes, separated tarsals and carpals, short heel, rather flat astragalus, and neither hoofs nor claws, but something between the two ; the bones of the forearm and leg are not so unequal as in the higher types, and remain entirely distinct from each other, and the ankle-joint is not so perfect as in many of them. In his teeth his character is thoroughly primitive. . . . " His structural superiority consists solely in the complexity and size of his brain.
Página 130 - ... been known to continue for many years in a small quantity of fluid enclosed between two glasses in an air-tight case. It is, however, greatly accelerated and rendered more energetic by heat ; and this seems to show that it is due either directly to some calorical changes continually taking place in the fluid, or to some obscure chemical action between the solid particles and the fluid, which is indirectly promoted by heat.
Página 49 - ... moon, the sea would long since have assumed a permanent state "of equilibrium. The action of these bodies continually disturbs "it, and it is sufficient to ascertain the oscillations which depend "on this action." Tiie above may, I think, be paraphrased and amplified thus : Gicen any initial condition (or "primitive state") of form and motion of the waters of the sea, the "general integral...
Página 155 - Prof. Wyman closes his essay by saying that " much error would have been avoided if those who have discussed the structure of the bee's cell had adopted the plan followed by Mr. Darwin, and studied the habits of the cell-making insects comparatively, beginning with the cells of the humble-bee, following with those of the wasps and hornets, then...
Página 240 - ... there is a stream of considerable size, which divides and flows down either side of the water-shed, thus discharging its waters into both the Atlantic and Pacific oceans. Having seen this phenomenon on a small scale in the highlands of Maine, where a rivulet discharges a portion of its waters into the Atlantic and the remainder into the St. Lawrence, I am prepared to concede that Bridger's " Two Ocean river
Página 174 - Fiske, in a most reasonable way, shows that " the prolonged helplessness of the offspring must keep the parents together for longer and longer periods in successive epochs ; and when at last the association is so long kept up that the older children are growing mature while the younger ones still need protection, the family relations begin to«become permanent. The parents have lived so long in company that to seek new companionships involves some disturbance of ingrained habits...