. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. >5 n> •' I f '^ A B Fig. 62 (left). — Chondriome, showing morphological similarity of the meristem of pea root (A) and of pancreas cells of gruinea pig (B), each fixed by Regaud's method and stained with iron haema- toxylin. A, plastids and chondriosomes indistinguishable; B, chon- driosomes and Claude Bernard granules. (After Cowdry). Fig. 63 (right). — Detail of chondriosomes (A) in pea root and (B) in mouse pancreas. X 1687. (After Cowdry). for they are of similar form. Although in most cases it is the chondri
. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. >5 n> •' I f '^ A B Fig. 62 (left). — Chondriome, showing morphological similarity of the meristem of pea root (A) and of pancreas cells of gruinea pig (B), each fixed by Regaud's method and stained with iron haema- toxylin. A, plastids and chondriosomes indistinguishable; B, chon- driosomes and Claude Bernard granules. (After Cowdry). Fig. 63 (right). — Detail of chondriosomes (A) in pea root and (B) in mouse pancreas. X 1687. (After Cowdry). for they are of similar form. Although in most cases it is the chondrioconts which become plastids, there are numerous excep- tions, and cases are found in which the granules, as well as the chondrioconts, become plastids. It may even happen in some cases that the granules alone form the plastids, whether the other ele- ments present have the form of chondrioconts or whether they also have the form of mitochondria. In the tuber of potato, for example, only granular mitochondria are found (Fig. 39) and it is through the agency of some of these that starch is elaborated. Furthermore, the distinction which we have made between the two categories of elements, , chondrioconts and granules, in the bud of Elodea canadensis and in the root of Cucurbita Pepo, is far from being general. Whether we can differentiate between the two cate- gories depends, in Elodea, upon the state of activity of the bud and the period at which it was collected. There are buds in which this distinction is much less clear, others where it can no longer be made. The difference in size which we have noticed between the starch-forming plastids and the chondriosomes in parenchyma cells of the pumpkin root may itself diminish or disappear. For ex- ample, in cells in which the starch grains have just been digested, the chondrioconts which elaborated them, grow thinner and are in- distinguishable from the other elements of the chondriome. Cells in the meristem of Elodea and
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