. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Guilliermond - Atkinson — 92 — Cytoplasm search (1912-1923), as well as by that of FRIEDRICHS (1923), that the meristem of the bud of Elodea canadensis does not contain chloroplasts. This is contrary to the findings of NOACK, whose error can only be explained by supposing that in his preparations he confused tissues already differentiated and containing chloro- phyll, with the meristem. It has been proved, besides, that among the elements which constitute the chondriome of meristematic cells in the phanerogams, it is impos
. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Guilliermond - Atkinson — 92 — Cytoplasm search (1912-1923), as well as by that of FRIEDRICHS (1923), that the meristem of the bud of Elodea canadensis does not contain chloroplasts. This is contrary to the findings of NOACK, whose error can only be explained by supposing that in his preparations he confused tissues already differentiated and containing chloro- phyll, with the meristem. It has been proved, besides, that among the elements which constitute the chondriome of meristematic cells in the phanerogams, it is impossible to distinguish those which will later become plastids, from those which will remain chondrio- somes. Both have the same shapes and histochemical character- istics. Cytological work on animals (Levi), as we have said, has established the fact that the chondriosomes are indeed permanent and clearly characterized elements of the cytoplasm. This is dem- onstrated, furthermore, by the research that we have done on the Saprolegniaceae, in which the absence of plastids makes this study more easy than in chlorophyll-bearing plants, and in which we have been able to follow the chondriome in liv- ing material during the entire de- velopment of these fungi. It is there- fore not possible, for the time being, to consider the chondriosomes as dis- similar elements, or as products of cellular metabolism (Allmantes). The theory of ARTHUR Meyer, who labels the chondriosomes Allinantes, has never been verified, and is today definitely invalidated. It has not been confirmed, either, that the plastids and the chondrio- somes of embryonic cells of phanero- gams can be differentiated by their dimensions, as was thought by MoT- tier who, without doubt, observed only cells already in the process of differentiation. Furthermore, our research has shown that the chondri- osomes which are not transformed into plastids are in no wise exclusively shaped as granules, as Meves believed. It sometime
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