132 The Botanical Gazette. [Marci 
: ‘ 4 b. 
Fig. 15. Upper end of the embryo-sac, with the pollen-tube absor 
ing we pee of the nucleus of one of the synergide, the latter be 
ing but lightly shaded. 
i : hbbyo-aac showing the two centrospheres of the on 
and those of the lower sperm-nucleus in their usual position at t 
Fig. 17. Upper end of the embryo-sac; the oosphere 1s bulged Pd 
on the side toward the pollen-tube; the centrospheres lie some 
tance above this protuberance. th the 
ig. 18. Conjugation of the nucleus from the pollen-tube wi ro 
oosphere. Above to the right is the other sperm-nucleus, and to 
left the remaining synergida. be still 
Fig. 19. Embryo-sac. The upper nucleus of the pollen-tube st! 
persists, as does also one synergida; while the oospore is in the st 
mented-skein stage, and the definitive nucleus of the embryo-sac 
nearly completed division. ee rt 
ig. 20. First two cells resulting from the division of the prea 
The nucleus from one of the synergidz appears at one side of the 
Fig. 21. Proembryo with three cells. The upper susp “7 
with its nucleus is becoming very much enlarged. In its uppée 
18. 
free in the embryo-sac. se 
ig. 23. Proembryo with five cells. The three nuclei in the embry 
sac are endosperm 
ig. 24. More advanced stage of the embryo, showing three susp — 
sor cells. 
