No. 3.] EGG OF ALLOLOBOPHORA FCETIDA. 545 



nuclear wall, and shows no indication of disintegrating (cf. I'liotos 4 and 6, 

 PI. XLI, for stained archoplasm at this stage). Fixative, Hermann's fluid. 



Photo 36, section {2^ ix) of a young oocyte, showing osmophile granules sur- 

 rounded by archoplasm ; three to the right, and one above the nucleus. These 

 granules are completely obliterated after the archoplasm is stained (cf. Photo 37). 

 Fixative, Hermann's fluid. 



Photo 37, the same cell shown in Photo 36, after staining with iron-hasma- 

 toxylin. The archoplasm is deeply stained and completely obliterates the osmo- 

 phile granules, which were sharply differentiated in the unstained preparation. 



Photo 38, section (3/u) of a young oocyte. The archoplasm still showing no 

 signs of disintegration. Two widely separated osmophile granules, only one of 

 them in contact with the archoplasm. Fixative, chromo-acetic, followed by osmic 

 acid. X 930 diameters. 



Photo 39, section (2i/i) of a growing oocyte. This large cell shows an increase 

 in the amount of archoplasm and in the number of osmophile granules, the inter- 

 mediate stages showing a gradual increase of both. There are archoplasmic 

 aggregations on the periphery and throughout the cytoplasm. For the varying 

 distribution of the archoplasm at this stage, see Photos 13, 14, and 15, PI. XLI. 

 Fixative, Hermann's fluid. 



Photo 40, section (z\ /x) of a growing oocyte. The archoplasm is scattered 

 through the cytoplasm, and has increased in amount with the growth of the 

 egg. There are also more osmophile granules present at this later stage of 

 development. For the varying distribution of the archoplasm at about this stage, 

 see Photos 17, 18, 19, 20, and 22, PI. XLI. Fixative, Hermann's fluid. 



Photo 41, section {2^ fx) through the cytoplasm of a large oocyte, first order, at 

 the distal end of the ovary. In these eggs the archoplasm is much more evenly 

 distributed, and the number of osmophile granules has increased enormously, but 

 it is a question whether they have increased more than the archoplasm or other 

 constituents of the cell. For an example of the distribution of the archoplasm at 

 this stage, see Photos 21 and 23, PI. XLI. Fixative, Hermann's fluid. 



Photos 42, 43, and 44, sections (2^/Li) of oocytes, first order, at the distal end 

 of the ovary. These eggs are further examples of what we interpret as the normal 

 size and distribution of the osmophile granules at this stage of development. 

 Their increase is scarcely out of proportion to the growth of the rest of the cyto- 

 plasm. In degenerating eggs, however, the osmophile substance is largely in 

 excess of all other constituents of the cell (cf. Photos 21 and 23, PI. XLI, for 

 stained archoplasm at this stage). Fixative, Photo 42, Hermann's fluid; Photo 43, 

 corrosive sublimate, followed by osmic acid; Photo 44, picro-nitric, followed by 

 osmic acid. 



Photo 45, section (2^^) of a degenerating oocyte, first order, at the same stage 

 of development shown in Photos 42 and 44. This egg was filled with masses of 

 osmophile substance such as we see in the photo, and the rest of the cytoplasm 

 is degenerating; it has shrunken away from the cell membrane, and not only the 

 archoplasm, but all parts of the cytoplasm appear to have been sacrificed to the 

 formation of these large masses of osmophile substance. Fixative, corrosive 

 sublimate, followed by osmic acid. 



Photo 46, section (2|^/i) through a space between three large oocytes. The 

 two black masses to the left are sections of blood which was tinted yellow by the 

 fixative. The rest of the black masses, as well as the granules, are intensely black 



