516 CHARLES W. HARGITT 
lost as chromatin, unless some may be recovered during phases 
of cleavage, as suggested in the previous paper. Some further 
reference to this feature will be made in a later section of this 
paper, in connection with the discussion of theoretical problems 
involved in the general subject. 
Incidentally it may be worthy of mention that in at least one 
case two germinal vesicles have been demonstrated in a given 
egg. So far as the writer is aware this is a rather rare occurrence, 
though probably not more so than that of hermaphrodite gono- 
phores, as described in the previous paper (p. 211). Fig. 23 is a 
careful camera sketch of these nuclei. There was not the slight- 
est evidence to show that there might have been a fusion of two 
oocytes in this case, as sometimes happens in other hydroids, 
the egg being only of average size. 
4. Nucleolar behavior. In the previous paper (p. 221), atten- 
tion was directed to some aspects of nucleolar changes associated 
with maturation. Among these that of vacuolation was partic- 
ularly mentioned, as was also that of the migration of the nucleolus 
from the nucleus into the cytoplasm. The latter feature is rather 
unusual, and is not probably of any large significance. More 
important is the fragmentation which is a rather common fea- 
ture. Prior to maturation the nucleolus exhibits various phases 
of vacuolation. In some cases several vacuoles of slightly differ- 
ing sizes appear, some of which may later fuse into a larger vacuole. 
In other cases one finds a single large vacuole which finally occu- 
pies almost the whole of the nucleolus, at which time it may hap- 
pen that the body collapses upon itself, or gradually goes to pieces, 
i.e., fragments. In other cases there may be in a given nucleus 
two nucleoli, one highly vacuolated and evidently degenerating, 
the other having all the appearance of a new organ, without signs 
of vacuoles.1 These changes usually occur while the nucleus is 
1 In this case the larger, vacuolated nucleus exhibited a most interesting phase 
of apparent fragmentation. Almost the whole organ comprised a single large 
vacuole, and adhering to the outer surface were numerous deeply staining spherical 
granules borne upon delicate pedicels, the whole resembling a sort of pin-cushion 
aspect. Just what significance such a condition may have in relation to nucle- 
olar metamorphosis, or its bearing on the problem of chromosome formation, as 
