THE MEIOTIC PHENOMENA IN BLAPS 73 
in the terminal cap, which is a zone occupying the distal end of 
each follicle, very often only those produced in its central area 
are apt to go through all the stages of spermatogenesis; while 
those lying in the periphery usually degenerate. Thus a stream 
of cysts, as it were, containing all the stages, is produced. Fur- 
thermore, the cells of a cyst usually do not appear in the same 
stage; this is specially true in the case of those dividing. One can 
find, for instance, even in the same section, all the stages connect- 
ing the metaphase with the late anaphase. This happens not 
only in the spermatogonia, but also in the spermatocytes, and 
owing to this fact more than one point which otherwise would 
appear puzzling has been settled beyond any doubt. 
The spermatogonial mitoses. Since in my first paper (14) I 
dealt extensively with the spermatogonial mitoses, it seems un- 
necessary to give a detailed account of them now. The main 
stages have been represented in figures 8 to 35, which speak for 
themselves. Only a few details are considered here, most of 
them outlined in my previous work. 
During the resting stage of the early generations of spermato- 
gonia, the chromatin is scattered throughout the nuclear cavity, 
forming irregular masses made up of granules, located near or 
at the periphery, in contact with the nuclear membrane. A 
large chromosome occurs in these cells, which retains more or - 
less clearly its individuality throughout the resting condition; its 
appearance varies greatly according to the size of the chromatin 
masses of which it is made up, which may be very small and reg- 
ular, placed along a thread (figs. 1, 2, and 7, a), or coarse and un- 
equal (figs. 3 to 5 and 7, b, c). In some cases it appears as a 
condensed, more or less V-shaped chromosome of ragged outline 
(fig. 6). Whether or not this body represents the X-chromo- 
some which later appears condensed in the spermatocyte is a 
question rather difficult to answer. However, the fact that it 
retains its individuality and that in the early spermatocytes a 
similar chromosome is found, which could be traced to the con- 
densed body of the later stages, makes this assumption highly 
probable. 
