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Wm. S. Marshall, 



been formed, it will be noticed that it is not equally distributed but 

 occupies the central portion. On the surface of the oöcyte there is 

 a rather dense finely granulär layer free from deutoplasm ; at the 

 distal end of the oöcyte there is a cone shaped mass of the same 

 substance, the base of the cone is at the end of the oöcyte its apex 

 extending down towards its middle and sometimes passing nearly 

 throngh the oöcyte (Figs. 84, 86 and 88, dotted lines). The basal 

 part of this cone corresponds to that part of the oöcyte which 

 lies nearest the nurse-cells and where the greatest activity is taking 

 place. Those parts of the oöcyte which are free from deutoplasm, 

 peripheral part and distal cone, contain these small nuclear-like bodies 

 and it may be they have something to do with this activity helping 

 to change the contents of the nurse cells into a substance suitable 

 for the oöcyte. 



The nucleus from an oöcyte having a diameter of 0,07 mm 

 contains a nucleolus, one or more masses of achromatin in which 

 are many darkly staining chromatin granules and an irregulär reti- 

 culum in which are small lightly staining bodies. Such an oöcyte 

 nucleus (Fig. 93) taken from the ovary of a nearly mature wasp- 

 not its oldest oöcyte- is similar to what we have already found in 

 the oldest oöcyte of a younger stage (Fig. 77 and 80). The nucleus 

 still retains its regulär form (Fig. 93) as do also the small nuclear- 

 like bodies near it. In older and larger oöcytes we notice an irregularity 

 in form and a change in structure (Fig. 94). The achromatin mass 

 in this nucleus, from an oöcyte 0,12 X 0,15 mm, stains with Heidex- 

 hain's iron-haematoxylin very darkly so that no darker granules can 

 be distinguished in it. The nucleolus is darker and often contains 

 one or more vacuoles. With the growth of the oöcyte the form of its 

 nucleus becomes irregulär; the large irregulär mass and the nucleolus 

 remain, the irregulär beaded Strands break up and a fine fibrillar 

 mass appears in the central part of the nucleus: here and there are 

 Short beaded rods, whether these latter are only a stage in the 

 distintegration of the Strands or new structures which may play a 

 further part in the history of the egg, we are unable to say, as here 

 our present iuvestigation stops. 



We have already noted the presence of a chromatin ring (G-iae- 

 DiNA [8]), in the cells. This occurs quite early in the development, 

 being seen in larval stages, but disappear shortly after synapsis. 

 It is a small, darkly staining ring which lies between two adjacent 

 cells; two may be found between the same cells (Fig. 101) or the 



