GAMETOGENESIS OP SACCOCIRRUS 41 



nitrate or osmic acid Golgi-body method, an appearance such ' 

 as shown in PL 3, fig. 19, is seen. Large numbers of crescent- 

 shaped bodies, such as were noted in the spermatocyte (PL 1, 

 figs. 6 and 7), occur throughout the cytopLism. In younger 

 oocytes the bodies of the Golgi apparatus are densely packed 

 and placed to one side of the cell (PL 3, fig. 20, ga). Such 

 Golgi elements eventually divide rapidly, and spread out, 

 as fine crescents or slightly elongated rods, through the cyto- 

 plasm of the full-grown oocyte (PL 4, fig. 32, ga). 



18. If the ovary be treated by a chrome-osmium method, 

 and stained in iron alum haematoxylin or acid fuchsin, fine 

 mitochondria become visible (PL 3, figs. 23, 24, 25, m). Such 

 mitochondria are difficult and sometimes impossible to see in 

 the youngest oocytes and the oogonia. 



19. In chrome-osmium preparations there are also to be 

 seen fine true yolk-spheres, characterized by the fact that they 

 go yellow-green in the fixative and do not stain in haematoxylin 

 or fuchsin. 



20. By centrifuging the oocyte, three layers appear, viz. an 

 upper layer formed of true yolk (greenish), a middle clear 

 protoplasm layer, and a lower layer mainly formed of nucleolar 

 deutoplasm, with a mixture of mitochondria. 



21 . In many oocytes an enigmatic body, much like a secondary 

 nucleus, was noted (PL 3, fig. 23, xn, and PL 4, fig. 30, xn). 



22. The oogonial cytoplasm is oxyphil, and during oogenesis 

 becomes basophil, and then again oxyphil in the full-grown 

 oocyte (p. 16). 



Intermediate Cells. 



23. In PL 1, fig. 3, is a cell found in a male Saccocirrus, 

 and it shows characters intermediate between an egg and 

 a spermatocyte (p. 20). 



Discussion. 



24. The above facts are discussed on p. 21, and also the 

 probable part played by mitochondria and Golgi bodies in 

 heredity (p. 33). 



