72 



The reactions, performed by Meyer in 1904, were in the main sub- 

 stantiated in 1913 by Sumbal '') and in tlie same year by Linde"). 

 LiNUE points out that there is not any method to fix the volutin so 

 as to prevent it from being ultimately dissolved in water at room- 

 temperature. Besides Mkyer himself also other investigators are 

 wavering in their opinion about the chemical nature of this sub- 

 stance. GuiLLiERMOND ■'') for instance says that "though Meyer's hypo- 

 thesis seems highly plausible, "aucune preuve decisive" has as yet 

 been given" (p. 307). We quote from Kohl's^) manual of yeast- 

 cells (p. 40) the following passage: "Concerning the chemical nature 

 we are still much in the dark. The assertions brought forward have 

 not yet reached beyond the hypothetical stage." 



Now, would it not be possible to settle this question with the 

 aid of a snbtler micro-chemical reagent than Meyer and his followers 

 had at their disposal? If volutin is a nucleinic-acid compound, it 

 would presumably be dissolved by the enzyme that splits up nu- 

 cleinic acid, i. e. nuclease. If this could be demonstrated, the sup- 

 position would be proved. In connection with other experience of 

 the action of nuclease on the nucleoproteins in the cell, I have also 

 examined the volutin of various hypho- and blastomycetes and, as 

 has been said elsewhere, I first made use of a nuclease prepared 

 from the spleen of the ox. These eff'orts came to nothing, as volutin 

 dissolves in water at bodily temperature inside the time required 

 for a nuclease digestion. In glycerin the activity of the nuclease 

 appeared to fall short. When following another way I came to the 

 conclusion that Meyer's suggestion was perhaps right, as I found 

 that the volutin was dissolved within a very short time by the 

 nuclease-action of the living cells themselves, when brought in con- 

 tact with coverslip-preparations fixed in alcohol. No such result was 

 achieved with cells that were killed by formol-vapours and conse- 

 quently had been deprived of their nuclease action. ^) 



The volutin-granules, which along with fat and glycogen often 

 occupy such a considerable space in the eel-plasma of these unicel- 

 lular organisms, prompted me to look at them more closely both 

 morphologically *and physiologically. The following questions arise: 

 Is there no other way to establish the chemical nature than the 



1) Zeitschr. f. allgem. Physiol. Bd XV, 1913, p. 456. 



2) Gentralbl. f. Bakteriol. Abt. II. Bd. XXXIX-, 1913—14, p. 369. 



3) Arch. f. Protistenkunde, Bd. XIX, 1910. 



*) Die Hefepilze 1907. Quelle und Meyer. Leipzig. 



5) For a description of these experiments with Ustilago maydis and a species 

 of Torula, see Anat. Anzeiger. Bd. XL VII, 1914, p. 312. 



