Gnetum africanum , with Notes on Gnetum scandens. 1135 
parenchymatous zone showing arrangement into radial rows (cf. Lignier’s 1 assise rayonnante ’)„ 
x 116. 
Fig. 8. Longitudinal section through apex of ovule, showing nucellar cap and ‘ tent-pole ’ of 
endosperm, t.p. = tent-pole; N = remains of nucellar tissue; T = tapetum; Li, = inner integu¬ 
ment. x 78. 
Fig. 9. Transverse section through micropylar tube at the base of the closed region ; a minute slit 
is just reappearing. The ovule is rather older than the one figured in the text (Text-fig. 9, p. 1113); 
the almost solid central core of cuticularized cells is probably due to the division and subsequent 
cuticularization of the epidermal cells originally forming the lining of the tube; the beginning of 
the cuticularization is seen in Fig. 15, PI. LXXXVII. The more or less definite layer surrounding 
the solid core represents what was originally the subepidermal layer ( s.e .). x 336. 
Fig. 10. Longitudinal section passing through base of inner and outer integuments at level of 
origin from nucellus. 1 = inner, M = outer integument; Tr, = tracheides at termination of a bundle 
running into the base of the inner integument, x 116. 
Fig. 11. Part of transverse section through mature ovule near its base. E = endosperm; N = 
remains of nucellus still fused with the inner integument; 0.1. = outer integument; p = outermost 
covering ; St, — branched fibres ; v.b. = vascular bundle; D = hypodermal strand of brownish tissue; 
p = palisade layer; F = fibrous zone, x 116. 
G. scandens. 
Fig. 12. Transverse section through closed micropylar tube of mature seed just below flange 
(Fig. 1 a). All the cell-walls are lignified. The epidermal cells are elongated and now fit tightly 
together, x 400. 
PLATE LXXXVII. 
Fig. 13. Longitudinal section through young ovule of G. scandens. Shows open micro¬ 
pylar tube with cuticularized lining. 
Fig. 14. Longitudinal section through young fertilized ovule of G. africanum in situ. Shows 
pollen chamber, and prolongation of strands of meristem into inner integument. 
Fig. 15. Longitudinal section through apex of older ovule (abortive). Shows closed micro¬ 
pylar tube, flange, beginning of sclerified nucellar cap, lignification of inner fibrous palisade in outer 
integument. 
Fig. 16. Transverse section through apex of outer integument of old fertilized ovule. Shows star of 
lignified tissue in outer integument, and slit-like micropyle. 
Fig. 17. Transverse section through node of axis of male inflorescence of G. scandens, showing 
anastomosis of bundles. 
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