64 
In the foregoing article only the questions relating to the 
-manner of cell growth are considered, and of these the principal 
ones are so familiar as to need no explanation in regard to the 
application of the theory here set forth. In a foot-note the 
author says: “The act of conjugation does not refute the prin-— 
ciple that all new formation takes place by division, as before this 
can occur, new cells are formed by division.” 
This naturally suggests another application than that made 
by Prof. Wiesner. The reviewer may perhaps be pardoned for 
briefly stating this possible application, as it seems to follow as a_ 
natural consequence of the new theory. 
If this new method of growth be applied to that of reproduc- 
tion, a reason is found for various facts not hitherto explained. 
Admitting that the process of growth consists of a division of the 
plasome and a subsequent increase in size by the assimilation of 
lifeless matter, may not the process of reproduction resemble this, 
except that the two halves of the divided plasome unite with the 
halves of other units? Thus in the case of conjugation, fusion of 
the two masses would mean, not simply a mingling of the mi- 
cellae of the protoplasm of different cells according to the present 
theory, but first, a division of the plasomes of both masses, then 
a reunion, such that the halves of the protoplasm of one cell 
would unite with those of the protoplasm of the other cell. This 
represents the highest form, or that found in the highest plants. 
Next below this may be assumed the process known as rejuven- 
escence, a cell throws off its wall, the protoplasmic plasomes di- 
vide, then reunite, each half with that of another unit, a new wall 
is formed and the life processes of the original cell are repeated. . 
Following this in the downward scale comes the process 
known as asexual spore production. The plasomes of a part of 
the protoplasm of a cell divide, reunite as in the latter case, and 
thus become endowed with a new energy and have the power to 
germinate into a new plant. ‘ Below this comes the form of re- 
‘production which is nearest to growth and in many cases dif- 
ficult to distinguish from it, viz.: vegetative reproduction, division 
of masses without the union of divided plasomes with each other. 
BiG. 
