286 J. He So MOORE: 
trosomes, is at first closely applied to that part of the nuclear 
wall within which the curious lopsided condensation of the 
chromatin goes on. 
21. The fine-meshed, tightly-coiled condition of the chromatin 
persists some time, but it gradually resolves itself into a coarse 
chromatic network on the nuclear periphery (figs. 37, 38). 
The strands of this network are sharply polarised towards the 
position occupied by the archoplasm and the centrosomes. 
The large oval nucleolus present in the resting cells of the 
first spermatogenetic period becomes now somewhat modified, 
both in position and character. Instead of being disposed 
casually along the nuclear circumference, it takes a position, 
generally, but not always, in line with the long axis of the 
archoplasm (fig. 37, ”.). Along this line there is still to be seen 
the secondary nucleolus (fig. 36, 37, m.') surrounded with a 
vacuole, which I described in § 19. 
These two peculiar forms of nucleoli are always to be found 
after the transition from the first into the second spermato- 
genetic period, and throughout all the generations of the 
latter. 
22. The archoplasm, which at first lies closely applied to 
the nuclear wall, during the early stages of the conversion 
of the first into the second spermatogenetic period, migrates 
away, quite into the cell body, while the two centrosomes 
which it contains, moving faster in the same direction, appear 
shortly on its exterior surface just beneath the membrane of 
the cell (fig. 37). 
V. The Divisions of the Second Spermatogenetic 
Period. 
23. The advent of the first division in the second spermato- 
genetic period is characterised by the strong polarisation of 
the chromatin, represented in fig. 37. The chromatic strands 
are seen on close examination to be composed of a thick core 
of innumerable microsomes, which, collecting together into 
groups, give to the strands their curious monilated appearance, 
