CYTOLOGy 6-30 



He considered the yeast vacuole to be homologous to the vacuoles 

 of higher organisms and did not consider it part of the nuclear ap- 

 paratus. In spite of the fact that he states that his tests for volutin 

 were the same as those specified by Meyer, the legends of his draw- 

 ings often indicate that the stain used was haemalum, which would 

 stain the mitochondria equally well. He states specifically that 

 metachromatin (volutin) passes from the vacuole of the yeast cell 

 into the spores. 



Wager and Peniston engaged in a controversy with Guilliermond 

 concerning the appearance of volutin in the cytoplasm. I have con- 

 cluded that metaphosphate does not appear in the cytoplasm of living 

 cells although it can be found in the cjrtoplasm of dead cells. Cas- 

 persson and Brandt (1941) have shown that ribose nucleoprotein is 

 always present in the cytoplasm, either as granules, which I have 

 identified with mitochondria, or dispersed, but they did not detect 

 nucleic acid in the vacuole with the ultraviolet microscope, suggest- 

 ing that it contained little nucleic acid. Since volutin is abundant in 

 the vacuole, volutin in the sense of Meyer (metachromatin-Babes, 

 Guilliermond) is different from the cytoplasmic ribose nucleoprotein 

 granules which Caspersson and Brandt have called "volutin" and 

 which I have identified with mitochondria. 



Volutin is distinguished by its ability to retain basic stains when 

 the cells are rinsed in dilute acid. When volutin is stained with 

 methylene blue or toluidine blue, it retains the stain after treat- 

 ment with 1 percent sulphuric acid. In addition to being "acid fast," 

 volutin has the characteristic of staining red or purple with meth- 

 ylene blue or toluidine blue, in contrast to other basophilic compon- 

 ents of the cell which stain blue with these dyes. Both metaphos- 

 phates and ester sulphates retain dyes after destaining and stain red 

 or purple with toluidine blue. Volutin is especially abundant in copu- 

 lating yeast and in the newly formed zygote nuclei (fig. 6-22). Volu- 

 tin is widely distributed in fungi and bacteria, while the estersul- 

 phates (Sylven) are apparently widely distributed in higher animals. 

 Wiame's work strongly suggests that the volutin in yeast cells is 

 metaphosphate, because the addition of the phosphate to the cell in- 

 creases the amount of volutin demonstrable in the cell, and extracts 

 from these heavily stained volutin -containing cells yield reasonably 

 large quantities of metaphosphate. There is, however, no cytologi- 

 cal means of distinguishing between metaphosphates and estersul- 

 phates. 



THE TRANSFER OF VOLUTIN FROM CHROMOSOMES 

 TO NUCLEOLUS 



The nucleolus and chromosomes can also be demonstrated with 

 the volutin stain. [The nucleolus is a conspicuous structure in the 

 nuclear vacuole. When present it is easily demonstrated with Lugol's 



