. Class-book of botany [microform] : being outlines of the structure, physiology, and classification of plants : with a flora of the United States and Canada. Botany; Botany; Plants; Plants; Botanique; Botanique; Plantes; Botanique. 138 THK EPIDERMAL. SSSv Colto ana Btoimta of tho epidormis of Ozalis violacea; and68(5, of Convallarla racomosa. 680. Cuticle. The surface of the epidermis at length becomes itself coated with a delicaio, transparent pellicle, not cellular, called the cuticle. It varies in consis- teeicy, being thicker and stronger in evergreen and succulent pliiiits. It s
. Class-book of botany [microform] : being outlines of the structure, physiology, and classification of plants : with a flora of the United States and Canada. Botany; Botany; Plants; Plants; Botanique; Botanique; Plantes; Botanique. 138 THK EPIDERMAL. SSSv Colto ana Btoimta of tho epidormis of Ozalis violacea; and68(5, of Convallarla racomosa. 680. Cuticle. The surface of the epidermis at length becomes itself coated with a delicaio, transparent pellicle, not cellular, called the cuticle. It varies in consis- teeicy, being thicker and stronger in evergreen and succulent pliiiits. It seems to be merely the outer cell wall of the epidermis thickened and separated from the newly-formed wall beneatli it. 681. The hairs which clothe the epidermis are mere expansions of its tissue. They may each consist of a single elongated cell, or of a row .1 cells. They may also be simple, or branched, or stellate, or otherwise diversified. 682. Glands are cellular structures serving to elaborate and contain the peculiar secretions of the plant, such as aromatic oils, resins, honey, poisons, etc. A gland may be merely an expanded cell at the summit of a hair, or at its base, and hence called a (glandular hair (Labiatae). Or it may be a peculiar cell under the epidermis, giving to the organ a punctate appearance, as in the leaf of lemon. Other glands are com- pound and either external (sundew), or internal reservoirs of secretion (rind of orange). 683. Stings are stiff-pointed, 1-celled hairs expanded at base into a gland containing poisonous secretion. An elastic ring of epidermal cells presses upon the gland so as to inject the poison into the wound made by its broken point (nettle). 684. Prickles are hardened hairs connected with the epidermis alone, thus differing from spines, which have a deeper origin. Exam- ples in the Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appear
Size: 1975px × 1265px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, booksubjectpl
