542 FOOT AND STROBELL. 



did not stain with the haematoxylin, but retained enough of the osmic to leave 

 a brownish yellow tint which photographs sharply. Fixative, picro-acetic, fol- 

 lowed by osmic acid. 



Photo 17, section (2^//) of a growing oocyte. Archoplasmic masses aggre- 

 gated near the nucleus, which is somewhat shrunken. Fixative, picric acid. 



Photo x8, section (2^^) of a growing oocyte, near the distal end of the ovary. 

 Small archoplasmic masses scattered through the cytoplasm. Fixative, corrosive 

 sublimate. 



Photo 19, section (2\ii) through the cytoplasm of a growing oocyte, near the 

 distal end of the ovary. Archoplasm massed at the periphery of the cell and 

 scattered through the cytoplasm. Many of the osmophile granules can be seen 

 (cf. Photo 16). Fixative, picro-nitric, followed by osmic acid. 



Photo 20, section {2\\i) through a growing oocyte, near the distal end of the 

 ovary ; preparation unstained. The archoplasmic masses retained enough of the 

 picric acid to give a sharp differentiation in the photograph. In this preparation 

 the osmophile granules are black, due to the subsequent treatment with osmic 

 acid. Fixative, picro-nitric, followed by osmic acid. 



Photos 21 and 23, sections (2^ /i) of a large oocyte, first order, at distal end of 

 the ovary. The archoplasmic masses are quite evenly distributed through the 

 cytoplasm. Fixative, Rabl's picro -sublimate. 



Photo 22, section (2\ fx) of two growing oocytes, near distal end of the ovary. 

 A large part of the archoplasm aggregated at the periphery. Fixative, Rabl's 

 picro-formalin. 



Photo 24, section (5 /x) of a very young oocyte, showing an archoplasmic mass 

 attached to the nuclear membrane. The chromatin which was present in the 

 nucleus is not in focus, the nucleolus alone being represented in the photo. 

 Preparation unstained and mounted in glycerine. Fixative, corrosive sublimate. 



Photo 25. The same cell shown in Photo 24, after the preparation had been 

 immersed for two hours in artificial digestion fluid, stained with iron-haematoxylin 

 and mounted in balsam. The photo shows that by the action of the pepsin the 

 cell has lost its membrane and cytoplasm, but nearly all the archoplasm remains 

 intact. 



Photo 26, section (5/x) of a young oocyte, with archoplasmic masses scattered 

 through the cytoplasm. Preparation unstained and mounted in xylol. Fixative, 

 corrosive sublimate. Many of the details in this photo were strengthened with a 

 pencil. 



Photo 27. The same cell shown in Photo 26, after the preparation had been 

 immersed for two hours in artificial digestion fluid, stained with iron-ha;matoxylin 

 and mounted in balsam. The photo shows that the cell and nuclear membranes 

 have disappeared, also a large part of the cytoplasm, while many of the archo- 

 plasmic masses still remain intact. 



