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Wm. S. Marshall, 



on, and we now find a few very irregulär achromatin masses in 

 whicli are tbe chromatin granules. Throughout the nucleus are 

 numerous delicate achromatin fibrils and a rather large nucleolus. 

 This latter, in slides stained with safranin and then well washed out, 

 is very lightly if at all, tinged, and with Heidenhain's iron-haema- 

 toxylin never stains so dark as the chromatin granules. The small 

 irregulär masses containing the dark chromatin granules begin to 

 fuse with each other, their number decreases but the few found are 

 larger. The achromatin fibrils become more and more distinct; finally 

 they show a beaded structure, these granules not staining nearly so 

 darkly as the chromatin granules within the masses (Fig. 77). The 

 Union of the masses goes on, and there finally may be but one large 

 one alone, or one or two small ones with it. 



We have already noted that in the Chamber formation the oöcyte 

 and the nurse-cells first group themselves together and there is a 

 Chamber common to all; only later do the two Chambers, egg and 

 nurse, become separated from each other. At first the nurse-cells 

 arrange themselves, not only distal to the oÖcyte, but also at its 

 sides, so that, excepting the proximal end, they Surround it (Fig. 78). 

 We find that even here there is a gradation in the arrangement of 

 the nurse-cells according to size, the smallest in each group are 

 distal, the largest proximal. This arrangement we find present in 

 all later stages. Epithelial cells are found in small groups at the 

 sides of the oöcyte, and generally a few of them both distal and 

 proximal to it ; a few are also scattered in with the nurse-cells. The 

 nucleus of the oöcyte is about the same as that we last figured 

 (Fig. 77) and the nurse-cell nuclei are similar to those we described 

 for an earlier stage (Fig. 62). 



A little later (Fig. 79) we notice that, due to an increase in the 

 size of the nurse-cells, they are closer together. More epithelial 

 cells are scattered among them and these are found along the margin 

 of the Chamber, or just above the oöcyte, where they form a small 

 group (GrROSs). The epithelial cells around the oöcyte have begun 

 to form a regulär follicle but as yet, lie only as a narrow girdle 

 around it; more of them have become columnar than in the last 

 stage. The structure of the nuclei of all the cells remains nnaltered. 



If we now pass over two or three Chambers and come to an 

 older one we notice that one of the greatest changes is in the size 

 of oöcyte and nurse-cells (Fig. 80) and that no special change has 

 taken place in the structure of any of the nuclei. The epithelial 



