Proceedings of the American Philosophical Society Held at Philadelphia for Promoting Useful Knowledge, Tom 35

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American Philosophical Society., 1896
 

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Strona 272 - And they said, Go to, let us build us a city, and a tower, whose top may reach unto heaven ; and let us make us a name, lest we be scattered abroad upon...
Strona 93 - WoFUL DECADE." — A WEDDING FEAST. — A CAPTIVE BRIDEGROOM. FOB untold ages Maine had been one unbroken forest, and it was so still. Only along the rocky seaboard or on the lower waters of one or two great rivers a few rough settlements had gnawed slight indentations into this wilderness of woods; and a little farther inland some dismal clearing around a blockhouse or stockade let in the sunlight to a soil that had lain in shadow time out of mind. This waste of savage vegetation survives, in some...
Strona 89 - Changes of any kind in the conditions of life," he repeats, "even extremely slight changes, often suffice to cause variability. Excess of nutriment is perhaps the most efficient single exciting cause.
Strona 93 - ... mossy trunks, toadstools and rank ferns, protruding roots, matted bushes, and rotting carcases of fallen trees. A generation ago one might find here and there the rugged trunk of some great pine lifting its verdant spire above the indistinguished myriads of the forest.
Strona 89 - natural selection " is in some respects a bad one, as it seems to imply conscious choice ; but this will be disregarded after a little familiarity. No one objects to chemists speaking of " elective affinity ; " and certainly an acid has no more choice in combining with a base, than the conditions of life have in determining whether or not a new form be selected or preserved.
Strona 94 - ... aquatic flowering plants are, as we have seen, still practically rootless, and they absorb the greater part of their food directly by the foliar parts; but the larger number of the higher plants absorb their mineral food by means of what has come to be a subterranean feeding organ and the foliar parts have developed into gasabsorbing organs and they take in water only when forced to do so under stress of circumstances. But as a mere feeding organ the root requires no fibrous structure. It is...
Strona 93 - Young seedlings in millions spring every summer from the black mould, rich with the decay of those that had preceded them, crowding, choking, and killing each other, perishing by their very abundance ; all but a scattered few, stronger than the rest, or more fortunate in position, which survive by blighting those about them. They in turn, as they grow, interlock their boughs, and repeat in a season or two the same process of mutual suffocation. The forest is full of lean saplings dead or dying with...
Strona 89 - The survival of the fittest." This epigram is an epitome of Darwin's law of natural selection, or "the preservation, during the battle for life, of varieties which possess any advantage in structure, constitution, or instinct." In most writings, these two phrases — "natural selection" and "the survival of the fittest...
Strona 98 - They became specialized and inelastic; and the highly specialized is necessarily doomed to extinction. Such remnants of a vanquished host remain to us in our single liriodendron, the single ginkgo, and sassafras, and the depleted ranks of the conifers. My attention was first called to this line of thought by contemplating upon the fact that cultivated plants differ widely in variability, and I was struck by the fact that many of our most inextricably variable groups — as the cucurbits, maize, citrus,...
Strona 93 - ... stronger than the rest, or more fortunate in position, which survive by blighting those about them. They in turn, as they grow, interlock their boughs, and repeat in a season or two the same process of mutual suffocation. The forest is full of lean saplings dead or dying with vainly stretching towards the light. Not one infant tree in a thousand lives to maturity; yet these survivors form an innumerable host, pressed together in struggling confusion, squeezed out of symmetry and robbed of normal...

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