Shaw . — The Fertilization of Onoclea. 277 
into the egg-nucleus could not be shown with the faint cyto- 
plasmic stains used at these stages. We may reasonably 
expect to find that they are left outside in the egg-cytoplasm, 
but it is a question which will require to be settled by 
actual observation. In Figs. 3 and 11, which were drawn 
before the structure of the free spermatozoid was understood, 
there is something in the egg-cytoplasm on the outer side 
of the egg-nucleus which strongly suggests by its general 
appearance that it is the remains of the sperm-cytoplasm, 
accompanied in the case of Fig. 3 by the cilia. The writer 
has lately observed, in a specimen stained with Heidenhain’s 
haematoxylin, something that looks like a loose bunch of 
cilia in the same position ; and in some horizontal sections 
the outer part of the egg-cytoplasm, when seen from the 
outer side, shows radiations which have a spiral twist, such 
as the cilia of the spermatozoid sometimes show when that 
body is viewed from in front 1 . 
The egg-nucleus at the beginnifig of fertilization, and all 
through the process, is in the typical resting condition. 
The nucleoli, for there are generally several, are the most 
conspicuous structures in the stained sections. They vary 
in size and present a peculiar porous structure. The linin 
appears as a delicate network which bears the very small 
chromatin bodies. This was not demonstrated for all stages, 
but the general appearance of the female nucleus is the same 
throughout the process, and in later stages some well-stained 
examples made it possible to observe the linin network 
and chromatin bodies minutely (Fig. 12). Nothing was 
seen to indicate that the whole nuclear c membrane/ if it 
may be called such, was dissolved. There were indications 
that it dissolves or is ruptured at the place where the sperm- 
nucleus enters. The most remarkable fact observed, and one 
about which there is no doubt, is that the sperm-nucleus 
enters the egg-nucleus before it changes in form or visible 
structure. This is clearly shown in the section represented 
1 Webber has shown (’97, 2, p. 227) that in the fertilization of Zamia the cilia 
are left behind soon after the entrance of the spermatozoid into the egg-cell. 
U 
