iit8 Tho day .— The Female Inflorescence and Ovules of 
Gnetum scandens. 
The resemblance between the oldest seeds of G. africanum and the 
mature seed of G. scandens is very close in most respects. The chief 
difference is the fusion of the two outer coverings of the seed to form one, 
the single covering thus formed having a double vascular supply. Karsten 1 
noted the variation in number of the integuments in various species of 
Gnetum , and enumerates three species with their two outer coverings fused 
(G. verrucosum , G. Rumphianum , G. ovalifoliuni) ; the other species he 
examined had an independent middle covering. It is probable that these 
three species, like G. scandens , would have three separate coverings when 
young. 
The middle covering (outer integument) is entirely composed of 
lignified cells, and forms a hard, stony layer; the different kinds of tissues, 
palisade layer, hypodermal strands, fibres, &c., being now only recognizable 
by the shapes of the cells composing them. 
The level of freedom of the inner integument is nearer the apex 
of the ovule than in the oldest seed of G. africanum , and the cavity 
between the micropylar tube and the nucellus is thus proportionately 
smaller. 
The micropyle is closed, as in G. africanum ; the solid mass of cells in 
the closed region is entirely lignified, as is also the greater part of the 
micropylar tube. There is altogether a great deal more lignification in this 
species than in G. africanum. It is not possible to say whether ligni¬ 
fication of the integumentary tissues would ever develop to such an 
extent in mature ovules of the latter species, but it seems probable that it 
would not, since the young ovules of G. scandens have already more 
thickened tissues than older ovules of G. africanum. 
V. Development of the Ovule. 
A. The youngest ovules among my material were those of G. scandens 
shown in Fig. 1, PI. LXXXVI. In these (Fig. 13, PI. LXXXVII) the 
micropyle is widely opened and fertilization has not yet taken place. The 
embryo-sac contains a few nuclei in a peripheral position, and disorganiza¬ 
tion at the apex to form a pollen chamber has hardly begun. The three 
coverings arise close together from the base of the seed. The outer cover¬ 
ing is already well developed, and is traversed by a network of vascular 
bundles. The middle and inner coverings are still undifferentiated ; more 
or less definite strands of meristem traverse the middle covering and run 
into the base of the inner. 
1 Karston: Cohn’s Beitrage, 1893, p. 377. 
