. The plant cell, its modifications and vital processes; a manual for students. Plant physiology; Plant anatomy; Plant cells and tissues. 84 THE PLANT CELL. 1« Crystals occurring in certain cells, 2. Crystalloids. 3. Cystoliths. 1. Crystals of oxalate of lime, Ca(C02)2, may occur in the following forms:— «• Raphides, or elongated aoioular crystals, found singly or in sheaves in the cells of the cortex in the stem of Draanna (see Fig. 67). They also occur in the root of Hyacinthus and many other plants. /3. Quadratic crystals occurring singly in cells of the leaf of Begonia. y- Clustered crysta
. The plant cell, its modifications and vital processes; a manual for students. Plant physiology; Plant anatomy; Plant cells and tissues. 84 THE PLANT CELL. 1« Crystals occurring in certain cells, 2. Crystalloids. 3. Cystoliths. 1. Crystals of oxalate of lime, Ca(C02)2, may occur in the following forms:— «• Raphides, or elongated aoioular crystals, found singly or in sheaves in the cells of the cortex in the stem of Draanna (see Fig. 67). They also occur in the root of Hyacinthus and many other plants. /3. Quadratic crystals occurring singly in cells of the leaf of Begonia. y- Clustered crystals, also occurring in leaf-cells of Begonia, and in other tissues (see Fig. 68). These crystals are distinguished from those of other salts by the fact that, on addition of dilute hydrochloric acid, they dissolve without effervescence, whilst they are insoluble in acetic acid. Oxalic acid is a bye-product of metabolism in the cell, and it combines with calcium to form calcium oxalate, which separates out, in this case, in the living cell.*. Fig. 69.—A Cystolith of Carbonate of Lime (CaCOj) foemed in an Epidermal Cell of the Leaf of Ficus elastica. Note the "core" of cellulose upon which numerous layers of carbonate of lime are deposited. 2. Crystalloids, or, as they are often called, spheroids, of a substance known as iuulin (a carbohydrate), separate out in the cells of the tubers or petiole of Dahlia when these are treated with alcohol. Inulin takes the place of starch or sugar in these cells. The spheroids have a peculiar concentric and radiating structure (see Fig. 71, a) which is very characteristic. Large spheroids of * Occasionally crystals of oxalate of lime are found in the walls of cells (mesophyll cells of Wellingtonia).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Haig, Haro
Size: 1892px × 1320px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectplantanatomy, bookyea
