PLATES XXII, XXIII & yj^VJ—conti. 



Tig. 10. — Three germ-cells, one of which shows a raultiuuclear condi- 

 tiou. The surrounding nuclei belong to the germinal epithelium. Acetic 

 acid. X 450. 



PLATE XXI 11. 



Pig. 11. — Two cells of germinal epithelium, each possessing two like 

 nuclei. Argentic nitrate, x 450. 



Pig. 12. — Pour epithelial cells, coloured after a preparation in nitrate of 

 silver. One cell has a nucleus in close contact with a very young germ- 

 cell {g. c). X 450. 



Pigs. 13, 14, and 15. — Sections showing the arrangement of the nuclei 

 in the epithelial cell-islands. In Pig, 15 two germ-cells are seen within 

 the epithelial layer, corresponding to the surface view in Pig. 7. X 450. 



Pig. 16 represents two germ-cells in a somewhat more advanced condi- 

 tion than is seen in Fig. 15. x 450. 



Pig. 17. — An epithelial island, as seen from surface of a preparation in 

 silver nitrate. X 450. 



Pig. 18. — A young ovum, lying in the stroma, and surrounded with 

 follicular epithelium, of which only five nuclei were to be seen, x 450. 



PLATE XXIV. 



Pig. 19. — Section of ovary wall, with an ovum ("24 mm.) in position. 

 The nucleoplasm has contracted away from the membrane and the germinal 

 dots, x 165. 



Pig. 20. — An ovum ('26 mm.) with its follicular epithelium, as seen in a 

 fresh condition. The dark patches on one side are aggregations of yolk- 

 spherules. X 165. 



Pig. 21. — An optical section of a portion of a follicle and ovum 

 ("87 mm.), showing the yolk-patches in little later stage of development. 

 X 450. 



Fig. 22. — Section of an entire ovum ("57 ram.), to show the arrange- 

 ment and appearance of the yolk-aggregations at an early stage, and a 

 peculiar condition of the germinal vesicle. X 100. 



Pig. 23. — A part of a section of an ovum ('9 mm.), showing the yolk- 

 patches at a time when they have come to occupy the greater portion of the 

 ovum. X 450. 



Pig. 24. — Section of an ovum (1'15 mm.) and its follicular wall soon 

 after the limits of the yolk-patches have disappeared, x 450. 



Pig. 25. — Same (1*4 mm.) at a later stage, x 450., 



Pig. 26. — Same in a nearly ripe condition, x 450. 



Fig. 27. — A germinal vesicle from an ovum measuring "57 mm. x 165. 



Pig. 28. — Same from an ovum '82 mm. in diameter, showing the ger- 

 minal dots in process of breaking up by division, x 165. 



Pig. 29. — Same from an ovum 1*48 mm. in diameter, after the concen- 

 tration of the granular remains of the germinal dots, x 165. 



