J 
366 Wisconsin Academy of Sciences^ Arts^ and Letters. 
In some instances a vacuole associated with a nucleus may arise 
without bringing about a division of the nucleus. In such a case 
the vacuole originated below the surface of the chromatin mass 
and gradually enlarges eccentrically, giving rise to a vescicular 
structure consisting of a vacuole with a single chromatin body at 
its periphery (fig. 3a). In this case the vacuole is not destined to 
play a part in nuclear division. In some cases the vacuole en¬ 
larges uniformly around the chromatin body, leaving the chromatin 
suspended within the vacuole (figs. 4f, 4g and 5d). Thus is ap¬ 
pears that numerous vacuoles of the cytoplasm arise from the 
chromatin bodies; they may or may not have divided nuclei as they 
were formed. 
In figures 4a~4k are represented a number of nuclei taken from 
the two gametes of a sexual apparatus. All show stages in nuclear 
division except figure 4d where the vacuole was formed at one side 
as described above. Figures 4c, 4f and 4g represent the type of 
structure in which the vacuole was formed by progressing on all 
radii of the sphere, leaving the chromatin body within the vacuolar 
sap. A nucleus thus suspended within the vacuolar sap forms a 
second vacuole within itself to bring about division (figs. 4f 
and 4g). 
During the process of nuclear division strands of protoplasm 
are frequently observed, extending across the vacuole from one 
chromatin body to another (fig. 4a). They vary considerably in 
different figures and do not always appear. Such strands are evi¬ 
dently formed by the chromatin. In some cases the strands con¬ 
necting the daughter chromatin bodies appear to be so closely asso¬ 
ciated with the vacuolar membrane as to cause the membrane to 
be somewhat flattened, to conform to the straight lines of the con¬ 
necting strands, and thus present a vacuole with a broken surface 
of flat faces rather than the curved surfaces of other vacuoles 
(figs. 4f, 4h and 4i). 
In many cases the ultimate destiny of a vacuole of a division 
figure is that it' becomes obliterated by an incorporation of the 
membrane with the slimy cytoplasm, and the space within becomes 
gradually filled with slimy cytoplasm, either reticulate or homo¬ 
geneous. Figures 4j and 4k represent such groups of nuclei after 
the vacuole has thus become obliterated. The group of seven nuclei 
represented in figure 4k evidently originated from two sister nuclei. 
The three in the lower portion of the group and to the left are 
