3l8 ORGANISATION IN SPACE AND TIME 



and the nucleolus as a further coacervate included within 

 the nucleus. Guilliermond says that the development of the 

 chondriosomes and their later transformation suggests that 

 they also are coacervates. According to I. N. Sveshnikova^^ 

 the same may be said of microsomes. Finally, according to 

 P. Makarov, the formation of chromosomes in the resting 

 cell before division suggests that they are coacervate-like in 

 nature. 



The process of development of vital-staining granules in 

 protoplasm may serve as an example of the formation of 

 droplets of one coacervate within the substance of another.*" 

 A. S. Troshin considers that the formation of granules of 

 secretion within glandular cells is generally similar in 

 mechanism to the formation of multiple coacervates. 



As we have already mentioned, the process of coacervation 

 leads to the formation of a boundary or surface separating 

 the coacervate from the equilibrium liquid. This is associ- 

 ated with the appearance of new surface phenomena and, 

 in particular, with the adsorption by the coacervate of various 

 substances present in the surrounding medium. 



Many organic substances are extracted almost completely 

 by coacervates from their equilibrium liquids. Even when 

 the concentration is as low as oooi per cent a coacervate may 

 sorb some substances from the water in which they are 

 dissolved. Some of the molecules which are sorbed by the 

 coacervate pass into its liquid by hydration and some become 

 associated with the colloidal particles themselves, sometimes 

 entering into chemical combination with them so that quite 

 substantial chemical alterations in the composition of the 

 coacervate may take place. 



The selective character of the sorption is very important. 

 Coacervates may accumulate large amounts of one substance, 

 collecting it from dilute solutions, while on the other hand 

 they may take up only very limited amounts of another, 

 although this is present in high concentration in the equi- 

 librium liquid. This peculiarity arises from the facts that, 

 on the one hand, the colloidal particles of the coacervate 

 themselves adsorb some particular substances specifically 

 while, on the other hand, the solubility of substances in the 



