. Plant life, considered with special references to form and function. Plant physiology. XEROPHYTES AA'D HALOPHYTES. 325 C. Adaptations for storing water. 440. I. Special cell contents.âThe simplest of these adap- tations is the presence of mucilage in the cells, arising from the cell-wall or developed in the cell-sap of various parts. (See *\ 5.) The presence of acids, tannins, and salts perhaps aids in the retention of water. 441. 2. Water-storing tissues.â{a) Flesliy plants, or succulents, are those which thicken their parts by the develop)- ment of an unusual amount of parcnch\nia, which c
. Plant life, considered with special references to form and function. Plant physiology. XEROPHYTES AA'D HALOPHYTES. 325 C. Adaptations for storing water. 440. I. Special cell contents.âThe simplest of these adap- tations is the presence of mucilage in the cells, arising from the cell-wall or developed in the cell-sap of various parts. (See *\ 5.) The presence of acids, tannins, and salts perhaps aids in the retention of water. 441. 2. Water-storing tissues.â{a) Flesliy plants, or succulents, are those which thicken their parts by the develop)- ment of an unusual amount of parcnch\nia, which contains a large quantity of cell-sap, and usually much mucilage. These thin-walled, mucilage-containing tissues form a reser- voir for the storing of water. In such ]olants the epidermis is very strongly water-proofed; the stems are thick, cylin- drical, prismatic or spheroidal ; tlie lea\es are wanting, or they are thick and llesh)-, cylindrical or broad (fig. 369), and arranged in rosettes. (li) In non-succulents, the epidermis itself may be greatly developjed as a water-storing tissue, or it nray form great numbers of bladdery hairs which are richly' supplied with water, as fig. '^^tZ^^^'vysLfcrvivum I'n t-lnp ivpU l-nnwii " i, tictorum'). fleshy leaves aiTanged in a m tne \\ en-knO'\\ n ice- rosette, with offsets fonned at the ends of special TlTi-if '' -,,-, n-Vii'/l-. fVi^ brandies. Tliese lieconie detached and form in- piauc, on WlilCll me dependent plants. About one half natural size.â 1 â 1 â i. 1 â 1 ⢠After tirav. nairs glisten like ice. In the first case, the epidermis, instead of forming a single layer of cells, may develop into several lavers, the lower ones large and thin-walled, as in begonias, figs, and pcpipers (fig. 370). The cells immediately under the epidermis sometimes become transformed into a water-storing , as in the oleanders (fig. 36S); or strips of tissue extending from the. Please note that these images are e
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