Structural Botany: Or, Organography on the Basis of Morphology. To which is Added the Principles of Taxonomy and Phytography, and a Glossary of Botanical Terms, Volume 2,Partie 1

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American book Company, 1879 - 442 pages
 

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Page 84 - These nre successively produced, enjoy a term of existence, and perish in their turn. Life passes onward continually from the older to the newer parts, and death follows, with equal step, at a narrow interval.
Page iii - This volume, on the Structural and Morphological Botany of Phaenogamous Plants, properly comes first. It should thoroughly equip a botanist for the scientific prosecution of Systematic Botany, and furnish needful preparation to those who proceed to the study of Vegetable Physiology and Anatomy, and to the wide and varied department of Cryptogamic Botany.
Page 326 - Laws of Botanical Nomenclature adopted by the International Botanical Congress held at Paris in August, 1867 : together with a Historical Introduction and a Commentary, by Alph.
Page 125 - On this peculiar arithmetical property .... depends the geometrical one, of the spiral arrangement, which it represents ; namely, that such an arrangement would effect the most thorough and rapid distribution of the leaves around the stem, each new or higher leaf falling over the angular space between the two older ones which are nearest in direction, so as to subdivide it in the same ratio in which the first two, or any two successive ones, divide the circumference.
Page 317 - The two elements of species are : 1. community of origin ; and, 2. similarity of the component individuals. But the degree of similarity is variable, and the fact of -genetic relationship can seldom be established by observation or historical evidence. It is from the likeness that the naturalist ordinarily decides that such and such individuals belong to one species. Still the likeness is a consequence of the genetic relationship ; so that the latter is the real foundation of species.
Page 326 - This is the common framework of natural history classification. All plants and all animals belong to some species ; every species to some genus ; every genus to some order or family ; every order to some class ; every class to one or the other kingdom.1 But this framework, although all that is requisite in some parts of natural history, does not express all the observable gradations of relationship among species. And even gradations below species have sometimes to be classified. The series is capable...
Page 238 - In a state of nature the flowers are incessantly visited for their nectar by hive- and other bees, various Diptera and Lepidoptera. The nectar is secreted all round the base of the ovarium; but a passage is formed along the upper and inner side of the flower by the lateral deflection (not represented in the diagram) of the basal portions of the filaments; so that insects invariably alight on the projecting stamens and pistil, and insert their proboscides along the upper and inner margin of the corolla....
Page 237 - ... five distinct sets of males. Two of the three hermaphrodites must coexist, and pollen must be carried by insects reciprocally from one to the other, in order that either of the two should be fully fertile ; but, unless all three forms coexist, two sets of stamens will be wasted, and the organization of the species as a whole will be incomplete. On the other hand, when all three hermaphrodites coexist, and pollen is carried from one to the other, the scheme is perfect : there is no waste of pollen...
Page 238 - ... upturned, and they are graduated in length, so as to fall into a narrow file, sure to be raked by the thin intruding proboscis. The anthers of the longer stamens stand laterally...
Page 259 - Commonly the pollen remains unaltered until it is placed upon the stigma. The more or less viscid moisture of this incites a similar growth, and also doubtless nourishes it, and the protruding tube at once penetrates the stigma, and by gliding between its loose cells buries itself in the tissue of the style, descending thence to the interior of the ovary and at length to the ovules. Fertilization is accomplished by the action of this pollen upon the ovule, and upon a special formation within it.

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