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Transactions of the Boyal Society of South Africa. 
EXPLANATION OF PLATES XLV— L. 
PLATE XLV. 
Fig. 
1. 6r. scandens. Diagram of longitudinal section of nncellus to show pollen-chamber 
and embryo-sac. x 30. 
2. G. africanum. Pollen-chamber partially blocked by papilla-like cells from micro- 
pylar tissue, x 180. 
3. 6r. africanum. p.c. Pollen-chamber, p.t. Pollen-tube. c. Degenerating tissue of 
nucellus. x 40. 
4. G. africanum. An unpollinated ovule, c. Cavities formed by degeneration of 
nucellar tissue, end. Embryo-sac filled with endosperm. x 32. 
5. G. africanum. A fertilised ovule containing many proembryos. Endosperm 
growing upwards into cavities (c.) formed by degeneration of nucellar tissue. 
Dotted area (figs, 1-6), active nucellar tissue, x 30. 
6. G. Gnemon. An ovule with several pollen-tubes (2?. ^.). S- Sperm-cell. end. Endo- 
sperm, pv. Pavement tissue, s.n. Free sac-nuclei (c/. fig. 21b). x 30. 
PLATE XLVI. 
7. G. Gnemon. Lower portion of a micropyle in oblique longitu.dinal section showing 
many pollen-grains, x 400. 
8. G. africanum. Portion of a pollen-chamber in longitudinal section showing three 
germinating pollen- grains, of which two retain the prothallial nucleus, ex. Split 
exine. x 700. 
9. G. africanxim. A pollen-grain and young tube showing generative cell and tube- 
nucleus. X 1200. 
10. G. africanum. A generative cell and tube-nucleus from a tube which has pene- 
trated to one-third of the depth of the nucellar cap. x 1200. 
11. G. Gnemon. A fertilised ovule showing large cavity (c.) above embryo-sac formed 
by destruction of nucellar tissue by pollen- tubes {'p.t.). x 30. 
12-15. G. afyicaniim. Binucleate sperm-cells (anterior ends directed downwards). 
Fig. 12 X 1720 ; the rest x 1200. Fig. 15. Plate xlvii. 
PLATE XLVII. 
16. G. Gnemon. Pollen-tube Avith uninucleate sperm- cell and tube-nucleus. Tip of 
tvibe is almost in contact with top of embryo- sac. x 1200. 
17. G. africanum. Portion of embryo-sac showing simultaneous division of free nuclei 
X 700. 
18. G. africanum. Lower part of embryo-sac showing endosperm-cells and free 
gamete-nuclei, x 400. 
19. G. africanum. Middle portion of an unfertilised sac showing the upper part of 
the septate endosperm and the lower portion of the free gametes (a little con- 
tracted). A mass of endosperm-cells {d.) formed by cell-division. A large 
compartment (c.) containing two free nuclei. x 420. 
