28 ■ Mary Blount. 



environment of the structure, and I cannot be sure that it is homolo- 

 gous with those illustrated in Figs. 12a and b, and 13. I think 

 the latter are supernumerary sperms. Riickert ('99, p. 671) dis- 

 cusses the question of inwandering female elements, and while he 

 thinks there is no absolute proof against such a phenomenon, he 

 has nothing to present in its favor. 





Fig. 12a. — A mass of spenu nuclei in tlie region of accessory cleavage in the 

 egg shown in Chart II A. Transverse section. The center of the blastoderm 

 is toward the right, a., thin layers of albumen atUiering to the egg. acp., planes 

 of accessory cleavage, vit. vitelline membrane. 1. Spermatozoen caught be- 

 tween two layers of albumen. 2. A sperm nucleus in the deepest part of the 

 plane of accessory cleavage. Leitz 4 j yV- *^rube length 140 mm. 





Fig. 12b. — From the same section as Fig. 12a. From the marginal periblast 

 to the left of Fig. 12a. vit., vitelline membrane, pvf., perivitelline fluid, sp., 

 sperm nucleus. Leitz 4/yV. Tube length 140 mm. 



Fig. 12a is taken from a transverse section of the egg shown 

 in Fig. 4 and Chart II. It is in the accessory cleavage, the right 

 hand side of the figure being toward the center of the blastoderm. 

 Fig. 12b is from the same section, but further peripheral in the 

 periblast. There were other cells between these two places. This 

 particular group of nuclei continued through ten sections (each 

 section 10 microns) with similar conditions in other parts of the 



