Lectures on the Elements of Botany: Containing the Descriptive Anatomy of Those Organs, on which the Growth and Preservation of the Vegetable Depend, Volumen1

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Longman, Hurst, Rees, Orme and Brown, 1822 - 688 páginas
 

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Página 203 - The fig-tree, not that kind for fruit renown'd, But such as, at this day, to Indians known; In Malabar or Decan spreads her arms, Branching so broad and long, that in the ground The bended twigs take root, and daughters grow About the mother tree, a pillar'd shade, High overarch'd, and echoing walks between...
Página 350 - ... juice of the plant, formed by the exposure of the sap to the light and air in the leaf, and returned from it by the vessels that pass down from the leaf into the interior bark, by which it is deposited, and we may add elaborated by the action of the vital principle inherent in this part of the plant. To determine this point, he removed narrow circles of bark from shoots of Apple trees, " leaving a leaf between the places where the bark was taken off; and on examining them frequently during the...
Página 3 - ... and it was not till the middle of the sixteenth century, that the sun of science again burst this thick cloud, and shed its rays upon the north of Europe.
Página 557 - ... and a third, thin and expanded, .encloses the other two, or forms the covering for both surfaces of the leaf. On a closer examination we find that the first of these parts is vascular, the second cellular, and the third a transparent cuticular pellicle. Admitting, therefore, that these parts are present in every leaf, although we may not be able to discover all of them distinctly, owing to the imperfection of our instruments ; we may conduct our inquiries into the structure of leaves, in reference...
Página 78 - It is well seen also by the aid of the microscope in the pith of many other plants. The petals of flowers are almost entirely composed of cellular texture, the cells of which are filled with juices fitted to...
Página 375 - ... the proper juice of which is seen exuding from different points of the pith, in a horizontal section of the stem. Little is yet known, with certainty, concerning the functions of the pith. It appears, on the whole, to be a mere reiteration of the cellular envelope, and subservient to the vessels which surround, and occasionally pass through it.
Página 321 - In the shoot we are now examing, cut iu the autumn, the bark when separated from the wood is about the 16th part of an inch in thickness, and appears to the naked eye, composed of 4 distinct parts. 1. A dry, leathery, fawn-colored, semi-transparent, tough membrane, which is the cuticle ; 2. a cellular layer which adheres, although not very firmly, to the cuticle, and is named the cellular integument ; 3. a vascular layer ; and 4. a whitish layer, apparently of a fibrous texture, which is the inner...
Página 131 - The root is that part of the plant by which it attaches itself to the soil in which it grow«, or to the substance on which it feeds, and is the principal organ of nutrition.
Página 90 - ... conducted through it ? The thread is sometimes double, or divisible into several others ; and Mirbel asserts, what may be considered as doubtful, that it is furnished with a glandular border. These vessels are found in great numbers in monocotyledonous plants, as in the centre of the ligneous threads, which exist in the stems of Grasses, and in Palms. They are numerous, also, in most herbaceous plants ; and particularly in aquatics of a lax texture. They are seldom detected in the root, and never...
Página 332 - ... contact. Grew, Malpighi, Du Hamel, and others, supposed that the liber annually changes, by hardening, into the alburnum or young wood, an opinion also maintained by Mirbel and some of the ablest phytologists, but which is founded upon mistaken principles. It is through the liber, however, that the matter in which the new wood is formed, which annually augments the diameter of...

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