24 



ATLAS OF THE FERTILIZATION AND KARYOKINESIS OF THE OVUM. 



Plate VII. Phototype 26. 



T/ic Karyokinetic Figure {42 minutes). 



The rod-shaped chromosomes are now arranged to form the equatorial plate. The section is extremely thin, and the 

 figure shows clearly the cyto-reticulum and the relation of the astral rays to it (cf. Text-fig. XIV.). In this specimen the 

 entire amphiaster is surrounded by a granular zone, in which the meshes of the reticulum are finer than elsewhere (but 

 this is not always the case). Here and there the astral rays can be traced, as linear rows of granules, directly through 

 this zone into the outer reticulum. 



^WlllilfiifSi^ 



Fk;. XIV. 



Fig. XIV. — The karyokinetic figure fully developed, with completely formed spindles and asters (1500 diameters). 



The chromosomes are arranged in the equatorial plane of the spindle to form the "equatorial plate." The centre of each aster is occupied by a reticular centrosphere. The rays are 



distinctly granular in structure, very closely set, and at their outer ends become continuous with the reticulum. (Phototype 26.) 



Plate VII. Phototype 27. 



The Karyokinetic Figure {j8 miiiutes). 



This specimen, slightly earlier than the last, shows more clearly the reticulated centrosphere in the centre of each aster. 



