4 
synergids are sisters, and an upper polar nucleus is lacking. 
Two chalazal nuclei have taken the position of an embryosac 
nucleus, and antipodals are missing. 
The Endosperm and the Embryo. 
Fertilization takes place in a normal way, the pollentube 
discharging its contents in one of the synergids (Plate III, Fig. 
25). One male nucleus fuses with the egg nucleus and the second 
male nucleus moves towards the “embryosac nucleus‘ (Plate III, 
Fig. 26). Up to this very moment the latter has retained its 
double character and so three nuclei are seen fusing, giving 
rise to the primary endosperm nucleus. 
Endosperm formation commences at once and soon a great 
many nuclei are present. They are especially numerous at the 
top end and some are found all along the walls of the em- 
bryosac. All the time the sac is rapidly increasing in size, but 
the fertilized egg shows no signs of any activity. Not until 
the seed has reached a length of about 4 mm. does the egg’s 
first division take place (Plate VI, Fig. 35: mature sac — and 
sac after second division of egg). 
Embryo development begins with free nuclear division. The 
egg nucleus divides without cell wall formation giving rise to 
a two-nucleate embryo (Plate IV, Fig. 27). This first division is 
followed by a simultaneous division of both nuclei, their 
spindles at a right angle. The four nuclei resulting from this 
division are not lying on the same level. Somitimes they are 
found in two succesive sections (Plate IV, Fig. 28) and when in 
one figure (Plate V, Fig. 29) they are still distinctly on separate 
levels. The free nuclear division goes on till a sixteen-nucleate 
embryo stage is reached (Plate V, Fig. 30). Then walls are formed, 
the 16-nucleate embryo thus developing into a 16-celled one 
(Plate V, Fig. 31). Simultaneous divisions have come to an end 
now, seven of the sixteen cells figured, containing one nucleus 
each, and eleven of them showing two nuclei. 
The endosperm is still without cell walls, the free nuclei 
lying embedded in a common mass of cytoplasm (Plate VI, Fig. 
33, 34). Cytoplasm however becomes more and more vacwo- 
