1 12 Oliver .■ — On the Structure, Development \ 
Fig. 19. Longitudinal section, slightly to right of antero-posterior median plane, 
showing insertion of upper ovule, ov? e . s., embryo-sac, with two cap-cells below 
it; m., mycropyle. 45/1. 
Fig. 20. Similar section, slightly to left of median plane, showing insertion of 
lower stalked ovule, ov? 45/1. 
Fig. 21. Longitudinal'section of a cleistogamic flower, with stigma sessile on the 
ovary, a. /., anterior lobe of stigma ; p. /., posterior lobe, which is reduced. Note 
that the reduced stigmatic lobe corresponds to fully-developed loculus of ovary 
and conversely. 45/1. 
Fig. 22. Antero-posterior section of stigma, and upper part of style, a. I ., 
anterior lobe ; p. posterior lobe ; v. b., vascular bundles. 
Fig. 23. Transverse section (A-B of 6 b) of anther after dehiscence, con., con- 
nective; f /., fibrous layer. 70/1. 
Fig. 24. Very young upper ovule, ov?, showing the nucellus and origin of thick 
integument. In the nucellus is the embryo-sac mother-cell, and one cell (c) 
lying below it, which has just been cut off from its lower end. ct., integument ; 
e.s.m.c., embryo-sac mother-cell. 480/1. 
Fig. 25. Embryo-sac, with three equal cap-cells (r 1 , c 2 , c 3 ), lying below it. 
Section taken from a flower not yet opened. 400/1. 
Figs. 26 and 27. Two sections of upper ovule, showing the embryo-sac, e. s., and 
three cap-cells (c 1 , c 2 , c 3 ), below it, together with the surrounding tissue of the 
ovule. In 26 the uppermost cap-cell, c\ is becoming obliterated; in 27 the 
lowermost, c 3 , is much larger than either c 1 or c 2 . In 27 notice also the pointed 
summit of the embryo-sac, where it abuts upon the micropyle, m. 450/1. 
Fig. 28. Embryo-sac at time of fertilization. The lowermost cap-cell is now 
much larger than c 1 or c 2 . In the micropyle is seen a pollen-tube,/.^. ant., 
antipodals ; c 1 , c 2 , c 3 , cap-cells ; e., egg-cell ; e. s., embryo-sac ; n. e. s., definitive 
nucleus of embryo-sac; p.t., pollen-tube; syn., synergidae. 450/1. 
Fig. 29. Embryo-sac, e. s., and cap-cells, c 1 , c 2 , c 3 , from the lower ovule at a 
slightly later period than that in 28. Notice especially that the lowermost cap-cell, 
c 3 , has elongated considerably, c 1 and c 2 remaining quite small. Only one 
nucleus was observed in the embryo-sac in this preparation, the others very 
probably being in another section, or fallen away. The figure is given, however, to 
show the elongated cap-cell, c 3 . 400/1. 
Fig. 30. Shows the ovule and embryo-sac soon after fertilization, The terminal 
cap-cell, c 3 , has become divided longitudinally, and now forms a large appendage 
to the embryo-sac. The egg-cell has developed into a suspensor terminated by an 
undivided embryo-cell. Large endosperm cells have already arisen within the 
embryo-sac. The ovule has elongated downwards considerably, c 3 , the divided 
and much enlarged terminal cap-cell ; emb., embryo ; end., endosperm ; m., micro- 
pyle; sp., suspensor; syn., synergidae; a. s., ant. spine. 150/1. 
Figs. 31 and 32. Somewhat later stages than that given in 30; references as 
before. Fig. 31, 30/1 ; Fig. 32, 22/1. 
Fig. 33. Enlarged view of section of appendage, c 3 , in Fig. 32. The base of 
the embryo-sac with endosperm, end., is seen, with the probable remains of the 
intermediate cap-cells, c l and c 2 , between it and c 3 . The nuclei are large and 
