. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Guilliermond - Atkinson — 166 — Cytoplasm posed of thymonucleic acid, like those of animal cells, which ex- plains why the Feulgen reaction is obtained just as well in plant, as in animal, nuclei. In the Saprolegniaceae, finally, we have found sphaerocrystals which appear to have some relation to the phosphoaminolipides. The vacuoles contain, as well as the colloidal material just discussed, numerous crystalloid substances. The most wide-spread of these are organic acids, halogen salts, nitrates and phosphates, sugars (sac
. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Guilliermond - Atkinson — 166 — Cytoplasm posed of thymonucleic acid, like those of animal cells, which ex- plains why the Feulgen reaction is obtained just as well in plant, as in animal, nuclei. In the Saprolegniaceae, finally, we have found sphaerocrystals which appear to have some relation to the phosphoaminolipides. The vacuoles contain, as well as the colloidal material just discussed, numerous crystalloid substances. The most wide-spread of these are organic acids, halogen salts, nitrates and phosphates, sugars (saccharose, glucose, fructose, etc.), heterosides and pig- ments. Among the halogen salts we must mention the presence of iodide in a dissolved state in the vacuo- lar sap of numerous marine algae (Rho- dophyceae and Phaeophyceae). Its local- ization in the vacuole may be demon- strated in vivo by cresyl blue. This pig- ment in the presence of iodized solu- tions forms red crystals (Fig. 113) ar- ranged in the shape of a bouquet (Sau- VAGEAU and Mangenot). Among the pigments may be mentioned the oxy- flavanol pigments which are very pale yellow in color and the anthocyanin pig- ments which are red, violet, or blue. Both types are extremely widespread in green plants. Anthocyanin pigments, when found in high concentration in the vacuole, may crystallize there in the form of needle-shaped crystals or sphaerocrystals (Fig. 114). These two types of pigment show histochemical characteristics closely allied to tannins (darkening with ferric salts, blackening with osmic acid). The flavins may also be cited. These are yellow pigments playing at the same time the role of hydrogen carriers and the role of Vitamin Ba. We have recently found them in great abundance in the vacuoles of a fungus Eremo- thecium Ashbyii where they crystallize in the form of needles or sphaerocrystals. The alkaloids are very wide-spread in the vacuoles of the phanerogams and may be recognized by testing with io
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