Structural botany

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American Book Company, 1879 - Botany
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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 240 - These flowers do not secrete nectar or emit any odor : from their small size, as well as from the corolla being rudimentary, they are singularly inconspicuous. Consequently, insects do not visit them ; nor, if they did, could they find an entrance. Such flowers are therefore invariably self-fertilized ; yet they produce an abundance of seed. In several cases, the young capsules bury themselves beneath the ground, and the seeds are there matured. These flowers are developed before, or after, or simultaneously...
Page 236 - ... 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 87 - It is incident to all this that leaves should be of only transient duration, at least in their active condition. 164. Defoliation. The leaves of most Dicotyledons and some Monocotyledons separate from the stem and fall by means of an articulation at the junction with the stem, which begins to form early in the season and is completed at the close. There is a kind of disintegration of a transverse layer of cells, which cuts off the petiole by a regular line, and leaves a clean scar, such as is seen...
Page 236 - ... 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 236 - ... inner sides of the hind legs, as is likewise the stigma of the long-styled form. The anthers of the mid-length stamens, and the stigma of the mid-styled form, are rubbed against the under side of the thorax and between the front pair of legs. And lastly, the anthers of the shortest stamens, and the stigma of the short-styled form, are rubbed against the proboscis and chin ; for the bees in sucking the flowers insert only the front part of their heads into the flower. On...
Page 342 - The essential points in nomenclature are : (1) to aim at fixity of names ; (2) to avoid or to reject the use of forms and names which may cause error or ambiguity or throw science into confusion. Next in importance is the avoidance of all useless creation of names. Other considerations, such as absolute grammatical correctness, regularity or euphony of names, more or less prevailing custom, regard for persons, etc., notwithstanding their undeniable importance, are relatively accessory.

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