200 MUNSON. [Vol. XV. 



ment. It has also been shown that in those young eggs which 

 grow more slowly, being formed in a later period of the devel- 

 opment of the parent organism, when growth is consider- 

 ably retarded, and when therefore it may be supposed to be 

 scantily supplied with nutriment, these granules are often com- 

 paratively scarce, often almost absent (PI. XIV, Fig. 32). 

 This fact suggests that the granules may have been used as 

 food for the living substance, and that this is analogous to the 

 appearance and disappearance of those granules which later 

 appear in connection with the vitelline-body. 



Growth of the Cytoplasm. 



The vitelline-body, as we have seen, is at first a central gran- 

 ule situated close to the germinal vesicle, surrounded by circles 

 of large microsomes, probably connected by linin strands, and 

 a system of fibers connecting the microsomes radially (PL XIV, 

 Figs. 45, 46). In many cases this spherical structure is seen 

 to become more granular, the granules being arranged concen- 

 trically, but yet closely packed. It may thus increase greatly 

 in size (PI. XIV, Fig. 56), while remaining refractive and appar- 

 ently homogeneous, staining a bright red in acid fuchsin, and 

 becoming surrounded by a zone of granules which retain the 

 blue haematoxylin stain (PL XV, Fig. 78). In later stages 

 this body may become still more enlarged, and consist of a 

 large number of granules staining like the microsomes of the 

 cytoreticulum and be surrounded by concentric or interwoven 

 fibers, which again are surrounded by still another zone of 

 granular substance (PL XV, Fig. "]"]). At the periphery of 

 the central granular body the meshes between the granules 

 may gradually increase so as to acquire the essential structure 

 of the cytoplasm (PL XIV, Figs. 32, 46) ; or else a number of 

 blue granules, like the chromatin of nuclei, are found within a 

 felted mass of fibers which at the periphery passes gradually 

 into the cytoreticulum (PL XV, Figs. 70, j6 ; PL XIV, 



Fig. S3)- 



In the absence of the blue granules the vitelline-body re- 

 mains a compact mass consisting of closely packed microsomes 



