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Wm. S. Marshall, 



of mitotic figures. With the increase in size of the oöcyte and its 

 Chamber, the number of follicle cells becomes greater. 



In the last stage we noticed that the nurse-cell nuclei, after 

 division has entirely ceased, assume a form which is, at this stage, 

 characteristic. Far up in this tiibule we find that the nurse-cell 

 nuclei are similar to those we have already described; the stage 

 where each possesses a number of large chromatin nucleoles, each 

 lying in a mass of achromatin (Fig. 41)^ predominates. Near that part 

 of the tubule in which synapsis nuclei are found (Fig. 57 syn)^ the 

 nurse-cell nuclei have assumed their permanent form (Fig. 60), an 

 irregulär achromatin mass at or near the center, Strands of achromatin 

 forming a network, and containing a number of darkly staining 

 chromatin granules. Proximal to this these same nurse-cell nuclei can 

 be found, and for some distance down the tubule they do not change 

 their form. At this place, or wherever this form of nucleus is found, 

 mitosis among the nurse cells has ceased. Paulcke (25) holds that 

 the nurse-cells in Apis must divide amitotically, this we never found 

 in Polistes. Gross (10) finds mitosis in the nurse-cells of Bombics, 

 but in Vespa describes the nuclei of the nurse-cells as dividing 

 amitotically, figuring some cells with two or three nuclei. When we 

 reach that part of the tubule (Fig. 57, position 61) in which the oöcytes 

 begin to arrange themselves regularly in a row in its center, we 

 notice that nearly all the nurse-cell nuclei have changed a little in 

 structure, and, instead of the Single nucleoius, there are now two or 

 three. Passing down the tubule the cells have, except the epithelial, 

 increased considerably in size, and in the nurse-cell nuclei there 

 are now a number of nucleoli (Fig. 62) ; these are still of about the 

 same size but, in proportion to the size of the nucleus, smaller. In 

 this place (Fig. 57, position 62) the nurse cells are grouped in regulär 

 Order distal to the oöcyte to which they belong; amongst them a 

 difference in size relative to their position is noticed, distally the 

 smallest, proximally the largest. As the Chambers grow this arrangement 

 becomes more and more prominent. They- continue to increase in 

 size, this being more noticeable than any increase in structure. Each 

 nucleus (Fig. 63) now contains a number of the large irregulär bodies, 

 nucleoli, which differ very much in depth of color; this is not only 

 due to different stains but with the same stain, and even within the 

 same Chamber, quite a Variation in this respect may be present. 

 They also differ very much in size in the different nuclei found within 

 any Chamber, many small ones is the commonest arrangement, yet 



