460 BOTANICAL GAZETTE [DECEMBER 
include small granules. An attempt has been made to trace these 
structures from their origin to their fate, in order that something 
regarding their nature and function might be determined. This 
complexity of structure is in contrast with the prophase of an ordi- 
nary mitosis, where only chromosomes, at most chromosomes and 
the nucleolus, are inclosed by the nuclear membrane. 
The dark vacuolate masses are most conspicuous just after 
fusion (fig. 27). In the early stages small refractive globules are 
scattered throughout the granular egg nucleus; later, these become 
inclosed in a gelatinous network (fig. 19), and next appear as pre- 
viously described. During the first mitosis they accumulate into 
several globular, vacuolate bodies (fig. 34). The latter decrease in 
volume or become distributed throughout the nucleus during meta- 
phase (fig. 46). At anaphase the irregular masses once more 
become conspicuous (fig. 51). When the daughter nuclei are 
formed, these bodies are not included, and soon disappear. The 
fact that they are extruded would seem to indicate that they are 
not fundamental nuclear material. The fact that they are stored 
up during the growth of the nucleus and decrease in amount during 
mitosis would suggest that they are simply stored food bodies. 
Two successive groups of intranuclear fibers become differen- 
tiated during the processes of fusion, and the first division after 
conjugation. The first is concerned with the approximation of 
chromosomes to be described later; the second with the first 
mitosis. While the two chromatin groups, from the egg and from 
the male nucleus, are still distinct, fibers which penetrate and 
surround these groups are organized (fig. 28). A union of the two 
groups of fibers results in the formation of a single spindle made 
up of large complex strands (figs. 29-33). The spindle drawn was 
60 win length. After the approximation of the chromosomes into 
pairs the spindle broadens; the fibers become less conspicuous, and 
finally disappear, leaving a group of irregularly arranged chromo- 
somes within the now much reduced nuclear space (figs. 43-45): 
Meanwhile the chromosomes migrate to the center of the nucleus, 
and soon the second set of fibers is formed (fig. 46). At first these 
are restricted to the region in which the chromosomes are situated; 
as the chromosomes move to the poles, the whole nucleus becomes 
