GERM CELLS IN THE ARTHROPODA 151 



by a cellular envelope. Increase in size takes place 

 synchronously in both the nucleus and the cytoplasm 

 of the oocyte, and a number of stages in this process 

 are illustrated in the accompanying figures. In 

 Fig. 46, 5 a strand of cytoplasm is shown extending 

 forward to the nurse chamber, and it is evidently by 

 means of this pathway that nutritive material is 

 conveyed to the oocyte. During the growth period 

 the nurse cells decrease in size until they occupy but 

 a very small space and the follicular epithelium 

 becomes very much attenuated (compare Figs. 46, A 

 and 47, D). 



The fully developed oocytes (Fig. 47, D) are more" 

 or less vase-shaped with a broad base (posterior), 

 a narrower " waist-line," and a slightly thicker distal 

 (anterior) portion. They are not so long and slender 

 as those illustrated by Silvestri, but perhaps this 

 shape is attained later when the eggs are laid. 

 Within the oocyte are two conspicuous bodies. At 

 the anterior end is a very large nucleus (n) which 

 almost completely fills that portion of the egg; it 

 contains a few scattered rods of chromatin. Near 

 the posterior end is a smaller but even more con- 

 spicuous body (Fig. 47, D, k) which stains very deeply 

 with iron-haematoxylin. This may be vacuolated 

 and irregular, showing signs of disintegration, as 

 shown in Fig. 47, or may possess a smooth outline and 

 be entirely homogeneous. It is undoubtedly of a 

 very tough nature, since it not infrequently tears out 

 of the egg substance when struck by the sectioning 

 knife. This obviously represents the "nucleolo" of 



