132 FOOT AND STROBELL. [Vol.11. 



a striking contrast of red nucleoli and centrosomes, with black 

 osmophile granules. 



One unfertilized oocyte, first order, contained eleven nucleoli 

 (.'') distributed in and near the spindle and throughout the cyto- 

 plasm. The acid fuchsin was subsequently removed from these 

 structures with 70/0 alcohol, and they could no longer be seen 

 without the aid of sketches to indicate their position, while the 

 black osmophile granules remained as sharply differentiated as 

 before. In unstained preparations (such as described above) 

 we have found these granules at all stages of the development 

 of the Q^g, from the smallest oocytes (or oogonia) to the seg- 

 menting ova, and in the former, one is occasionally found so 

 exactly in the center of the yolk nucleus that in a stained 

 preparation it would be unhesitatingly pronounced a centro- 

 some. Tiny osmophile granules are often seen within the 

 attraction spheres, spindle, and cones, though they are/^r more 

 numerous throughout the rest of the cytoplasm. In some cases 

 one, two, or more osmophile granules have been seen apparently 

 in the exact center of a sphere (Text-fig. I). Throughout 

 the rest of the cytoplasm, both their distribution and form vary 

 greatly, even at exactly the same stage of the development of 

 the Q^^^. As to distribution, they are sometimes quite evenly 

 distributed throughout the cytoplasm (Text-fig. I), and again 

 large areas appear to be entirely free from them. As to size, 

 they are sometimes tiny microsomes (Photo. 8 and Text-fig. I), 

 and again many of them are as large and homogeneous as 

 nucleoli (Photo. 12), while in many cases they appear as masses 

 — aggregations of individual granules (Photo. 13). Whether 

 any one of these conditions is distinctive of the normal Q<g^^ we 

 are unable to determine at present. 



There are equally marked variations in their response to 

 stains ; after a short immersion, iron haematoxylin removes the 

 blackening caused by osmic fixatives — and, as a rule, it does 

 not stain the granules. After prolonged immersion (three days) 

 the osmophile granules show only a faint indication of the stain, 

 and in these cases, when mounted in xylol balsam, they entirely 

 dissolve out of the sections {cf. Photos. 13 and 14). In excep- 

 tional cases, however, they have formed an insoluble compound 



