430 TorRREY: CYTOLOGICAL CHANGES 
as a rule, at the height of secretion these cells are much swollen. 
The nucleus becomes greatly enlarged and distorted, often sending 
out pseudopodial processes. As a general rule there is.a loss of 
staining power in the nucleus during secretion. In the end the. 
cytoplasm is much shrunken and the nucleus and nucleoli com- 
pletely disappear. The nectar begins to appear at the end or just 
outside the end of the cell. In this case the nucleus seems to — 
play a very active réle and bears a strong resemblance to the be- 
havior of the nucleus during the secretion of diastase. In both 
there is a final disappearance of the nucleus after the cell has ex- 
hausted itself by its long-continued secretions. In both also there 
is a swelling of the cell during the formation of the secretion. It 
seems not unlikely that this swelling is brought about by osmosis 
set up by some substance secreted within the cell at this time. 
The diastase, being of a proteid nature and consequently of high « 
molecular weight, would not be, even if in solution, as active 
osmotically as other less complex substances, as for instance, Of 
ganic salts or acids, which, De Vries has shown, exercise a strong 
osmotic attraction when present in the cell. Nevertheless the 
swelling takes place when the nucleus has become completely filled 
with these granules. A possible explanation of this phenomenon 
may be that some organic acid is formed during the great meta- 
bolic activity of the cell. The fact that diastase, in order to be 
especially effective as a ferment, must be dissolved in a liquid with 
a distinct, but not too strong acid reaction, lends support to this 
hypothesis. 
A comparison of the secretory processes in plants with th 
in the animal kingdom, where the literature is much more com 
plete, is certainly of interest. Mathews (’99) has studied the 
secreting cells of the pancreas very carefully. He describes the 
pancreas cell as divided into two zones, a granular inner and Bs 
striated outer. The fibrils of the outer zone arise in the chromatin 
and end in the cytoplasm of the inner (granular) zoné. “ The 
chromatin has, then, formed a highly complex substance probably 
a nucleo-albumin (the cell thread or fibril) which splits into at least 
two constituents, one of which forms the granules, and the other 
a reticulum. The granular substance is perhaps further alt 
and ultimately forms the zymogen.” The interesting fact from @ 
ose . 
