434 THE CONTRACTILE VACUOLE 



fixation occurs at diastole, the vacuole appears to lie within the ring. 

 The ring does not collapse at systole, but remains more or less un- 

 changed. The vacuole is believed to be formed by the flowing together, 

 jor coalescing, of small droplets (Sammelvacuolen) which form within 

 the substance of this ring. In Dog/elella the osmiophilic material is in 

 the form of a ring around the vacuole, resembling, as Nassonov de- 

 scribes it, the rings around the planet Saturn. On contraction of the 

 vacuole, the ring remains essentially unaltered, showing a certain amount 

 of elasticity. The vacuole seems to arise as a result of the coalescing of 

 numerous droplets of fluid, just as in Chjlochn. These two forms, as well 

 as many others described by other authors, represent a separation of the 

 Golgi apparatus from the vacuole, although the close functional associa- 

 tion remains. Nassonov's conception of this close functional association 

 is expressed in a third publication (1926), in which he states that the 

 Golgi apparatus serves as a mechanism for collecting certain materials 

 from the cell substance and preparing them in such a way that they 

 can be discharged from the cell by the vacuole. To do this the Golgi 

 apparatus need not be a part of the vacuole system, nor even in direct 

 contact with it. This conception represents an important departure from 

 the first, in so far as morphology is concerned, but does not alter the 

 essential physiological relationship. Further evidence that such is the 

 function of the metazoan Golgi apparatus was obtained from experiments 

 in which the dye. Trypan blue, was injected into mice. On examination 

 of sections taken from the livers and kidneys of these mice, it was found 

 that the dye was concentrated in that region of the cells of the liver 

 and of the convoluted tubules of the kidney in which the Golgi apparatus 

 is situated. Distribution of mitochondria in these cells was found to be 

 quite different, indicating that these structures are not intimately associ- 

 ated with the collection of the dye. 



Some authors summarily reject the idea of a relationship between 

 vacuole and Golgi apparatus, solely on the ground that the wall of the 

 vacuole proves not to be osmiophilic. However, some of these same 

 authors present evidence which supports the idea of a physiological 

 relationship, even though the actual identity of the two structures is dis- 

 proved. Nassonov himself was among the first to demonstrate that by 

 no means all contractile vacuoles have osmiophilic walls, but this does 



