Natural Science, Volumen3Macmillan & Company, 1893 |
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Página 65 - When we reflect on this struggle, we may console ourselves with the full belief, that the war of nature is not incessant, that no fear is felt, that death is generally prompt, and that the vigorous, the healthy, and the happy survive and multiply.
Página 148 - Patagonia, he saw these birds swimming several times from island to island. They ran into the water both when driven down to a point, and likewise of their own accord when not frightened : the distance crossed was about two hundred yards. When swimming, very little of their bodies appear above water; their necks are extended a little forward, and their progress is slow. On two occasions I saw some ostriches swimming across the Santa Cruz river, where its course was about four hundred yards wide,...
Página 243 - To multiply and record observations, and patiently to await the result at some future period, was the object proposed by them ; and it was their favourite maxim that the time was not yet come for a general system of geology, but that all must be content for many years to be exclusively engaged in furnishing materials for future generalizations.
Página 65 - ... the animal world, is the very reverse of the truth. What it really brings about is the maximum of life, and of the enjoyment of life, with the minimum of suffering and pain. Given the necessity of death and reproduction — and without these there could have been no progressive development of the organic world — and it is difficult even to imagine a system by which a greater balance of happiness could have been secured.
Página 65 - On the whole, then, we conclude that the popular idea of the struggle for existence entailing misery and pain on the animal world is the very reverse of the truth. What it really brings about is the maximum of life and of the enjoyment of life with the minimum of suffering and pain.
Página 294 - ... of the pulmonary tissue, in such a way as to render this fundamental process, which, since Lavoisier, has justly been regarded as one of the most important in physiology, much more complicated than we for a long time supposed it to be. In like manner Heidenhain has proved that the process of lymphatic absorption, which before we regarded as dependent on purely mechanical causes — ie, differences of pressure — is in great measure due to the specific energy of cells, and that in various processes...
Página 299 - I mean what is called exceptional migration, not the mere wanderings of waifs and stravs, nor yet the uncertain travels of some species, as the crossbill in search of food, "but the colonising parties of many gregarious species, which generally, so far as we know in our own hemisphere, travel from east to west, or from south-east to north-west. Such are the waxwing...
Página 295 - Instead, therefore, of acceding to the request to ' hurry up ' we make a demand for more time." Professor Poulton : Presidential Address to the Zoological Section, 1896. " Our argument does not deal with the time required for the origin of life, or for the development of the lowest beings with which we are acquainted from the first formed beings, of which we know nothing. Both these processes...
Página 294 - ... on either side, natural philosophy (including chemistry) and psychology. As regards the latter I need add nothing to what has already been said. As regards the former, it may be well to notice that although physiology can never become a mere branch of applied physics or chemistry, there are parts of physiology wherein the principles of these sciences may be applied directly. Thus, in the beginning of the century, Young applied his investigations as to the movements of liquids in a system of elastic...
Página 90 - The mollusc was on a colony of Leptoclinum maculatum, in which it had eaten a large hole. It lay in this cavity so as to be flush with the general surface ; and its dorsal integument was not only whitish with small darker marks which exactly reproduced the appearance of the Leptoclinum surface with the ascidiozooids scattered over it, but there were also two larger elliptical clear marks which looked like the large common cloacal apertures of the Ascidian colony.