To /nee p. 123.1 



PLATE III. 



Plate ill. (Stages in the Maturation of the Enibryn-sac). 



1. A photomicrograph of the embryo-sac and its nucleus at thf stnue where the latter 

 is about to undergo its first mitotic division {Liliiiin). 



2. A photomicrogi'aph showinK the completed first division (Li/ii'iii). 



3. A slightly later stage than '1, showing the completed daughter-nuclei. 



4. End of the second division, four nuclei being now present. 



The next stage would he that where each of the nuclei in 4 have divided again, leading 

 to the presence of eight nuclei, four at each end of the cmbryo-siic 



