. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Chapter XIV 151 — The Vacuolar System these leaflets (Fig. 92) there are chondriosome-shaped vacuoles con- taining a substance which, when preserved with mitochondrial methods, becomes yellow, but which may be stained by iron haema- toxylin and which, if the destaining is not carried far enough, ap- pears black. This would make one think that these bodies corre- spond to chondriosomes impregnated with anthocyanin. In reality, as we were able to demonstrate by later work, they are vacuoles containing tannin with which antho
. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Chapter XIV 151 — The Vacuolar System these leaflets (Fig. 92) there are chondriosome-shaped vacuoles con- taining a substance which, when preserved with mitochondrial methods, becomes yellow, but which may be stained by iron haema- toxylin and which, if the destaining is not carried far enough, ap- pears black. This would make one think that these bodies corre- spond to chondriosomes impregnated with anthocyanin. In reality, as we were able to demonstrate by later work, they are vacuoles containing tannin with which anthocyanin is associated. Now, tannin, like the lipide substance of the chondriosomes, is rendered insoluble with fixatives containing potassium bichromate, and may be stained by iron haematoxylin. On the other hand, the study of plants in which anthocyanin is not associ- ated with tannin, makes it possible to observe that this pigment is not preserved by mitochondrial techniques and that the young chondrio- some-shaped vacuoles in which pigment forms do not stain with mitochondrial methods. Therefore, Dan- GEARD, instead of correcting a partial error committed by us, made the mistake of gen- eralizing it. Let us examine in more de- tail the development of the vacuoles in the phanerogams. In the barley root (Fig. 94), for example, the phenomena studied by Dangeard and then by us, are particularly clear. If a very young root of a seedling is studied in a solution of neutral red by crushing the root gently, in such a way as to dissociate the cells without injuring them, numerous minute elements are seen in all the cells of the meristem. They are scattered about in the cytoplasm and are stained deeply and homogeneously by the dye. In the very young- est cells these elements are all small granules but they soon elongate to undulous filaments which often afterwards anastomose into a network. By their form and their dimensions these ele- ments show a striking resemblance to the chondri
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