386 ; KING. [VoL. XIX. 
the nuclear membrane or distributed on the linin fibres which 
form an irregular reticulum. The nucleus contains several 
deeply staining nucleoli of various sizes which are suspended 
in the meshwork of the reticulum or held against the nuclear 
membrane. In preparations stained with safranin and gen- 
tian violet the larger nucleoli invariably take the safranin 
while the rest of the nucleus is stained blue with the gentian 
violet, and these bodies must, therefore, be considered as 
plasmosomes; the very small nucleoli, which are found chiefly 
at the points of intersection of the linin threads, are karyo- 
somes since they take the chromatin stain. In the cytoplasm, 
which stains very faintly and appears somewhat reticular, 
there is a vitelline body (Fig. 20, V); but I have not been 
able to find any traces of a centrosome or of an attraction- 
sphere in this or in any later period in the development of the 
oocyte. As there are no centrosomes at the poles of the ma- 
turation spindle (King, 51), it seems probable that the egg 
centrosome disappears after the last oogonal division and that 
the attraction-spheres found at the poles of the segmentation 
spindle are formed in conjunction with the sperm-nucleus, 
probably under the influence of the centrosome imbedded in 
the substance of the sperm-head. 
As the odcyte enlarges its outline becomes more regular and 
much more distinct. The nucleus, which measures about 0.0! 
mm. in diameter at this time, soon assumes the rounded form 
which it retains up to the maturation period (Fig. 21), and 
its reticulum appears continuous and much more sharply de- 
fined than at an earlier period (Fig. 22). The number of 
nucleoli is not appreciably increased during the early growth 
period of the oocyte. 
V. SYNIZEsSIS AND Post-SYNIZESIS STAGES. 
Although the stage in the development of the oocyte shown 
in Fig. 22 is practically at the beginning of the growth 
period it corresponds, apparently, to the stage at the end of the 
growth period of the spermatocyte (King, 52; Fig. 15). In 
