551 



conspicuously related to a marked polarization of the chromosomes 

 their focus being represented by the centrosomes and archoplasm taken 

 together. 



In the cells after the penultimate division, the archoplasm is only 

 conspicuous by its absence, its disappearance being directly connected 

 with an extrusion of the entire spindle — or rather intra-zonal — fibres 

 as a fusiform mass between the daughter cells (Fig. II). In the centre 

 of this mass there are to be found 3 — 6 small chromatic particles 

 arranged as an equatorial transverse band (fig. 26), conspicuous only 

 when the mass intervening between the cells is of considerable length. 

 The chromatic particles of which it is composed have all the appearance 

 of being the unclaimed central moiety of the chromosomes at the points 

 of their division (fig. 3&) and they thus possess a striking similarity 

 to certain bodies described by Boveri in connection with a possible 

 reduction process in the embryos of A scar is 1 ). 



At the same time it can hardly be doubted that they are equally 

 homologous with the "intermediate body" described by Flemmino. 

 If they are so, however, the homology he claimed between these 

 bodies and the cell 

 plate of plants and 

 the lower orders of 

 animals , seems to 

 me to vanish; be- 

 cause, so far as I am 

 aware , where this 

 structure exists it 

 is always the fore- 

 runner of the divi- 

 sion wall of daughter 

 cells, while the little 

 chromatic particles 

 are quite indepen- 

 dent of the formation 

 of a new bounding 

 membrane in the 

 cells of Scy Ilium. 

 Round the daugh- 

 ter nuclei formed by 



the penultimate division, are a number of small chromatic masses, found 

 on examination to be intimately related to a vacuolation of the cyto- 



III 



_/-- tr 



^a 



1) Gesellschaft für Morph, uod Phys., Bd. 8, 1892, p. 114—125. 



