ii26 Thoday.—-The Female Inflorescence and Ovules of 
posed of two layers: the outer, thick-walled and more or less clearly palisaded 
throughout, shows some sign of expansion at the tip of the ovule (Fig. 4, 
PL XXVIII, Wieland); the inner layer, which is composed of 4 string 
elements ’, probably corresponds to the fibrous layer in Bennettites, and is 
similarly prolonged downwards into the peduncle. 
In Gnetum the integument is also made up of two layers. The 
outer layer contains alternating vertical strands of parenchyma and dark 
coloured tissue, and is expanded at the apex of the integument, but is 
not thickened. In G. africanum and G. scandens there is only an indication 
of a radial arrangement of the cells at the apex, similar to that occurring in 
Bennettites, but in G. Gnemon 1 this is much more marked. The inner layer 
in G. africanum and G. scandens consists of a palisaded thin-walled layer, like 
that recorded in Bennettites , and a fibrous or stony layer, also as in Bennet- 
tites and Cycadeoidea : the arrangement of the latter layer appears to be 
exactly similar to that described in the fossil seeds ; it extends downwards 
into the stalk of the ovule, where it passes inside the vascular bundles and 
forms the pith of the upper portion of the peduncle, in the integument its 
cells are elongated and run irregularly in the horizontal direction, while in 
the peduncle they become short and very thick-walled. The fibrous layer 
is lignified in the peduncle of the quite young ovule, and in G. africanum 
at the apex of the seed also, where it forms a palisade layer. In the old 
ovule of G. africanum this layer shows signs of lignification throughout: 
in the mature ovule of G. scandens the whole inner integument is lignified. 
The distribution of the fibrous layer at the apex of the seeds in 
Bennettites Morierei is another point of resemblance to G. africanum , 2 It 
will be remembered that the former seed has four or five wings, while the 
latter has not. In both, however, the fibrous layer develops four or five 
wings which project outwards, and in B. Morierei extend into the outer 
wings. A comparison between Fig. 16, PI. LXXXVII, of this paper and 
Lignier’s Fig. 6, p. 41, &c., speaks for itself. 3 The wings of fibres in both 
seeds decrease in prominence lower down, forming small projecting angles 
which gradually die out, till the layer of fibres forms a smooth zone ; cf. Text- 
figs. 7 C, and 10 of this paper with Lignier’s Fig. 7, p. 42, Fig. 45, PI. IV, &c. 
Opposite each of the wings of fibres in G. africanum is a vascular 
bundle; Lignier could not certainly distinguish any vascular bundles in the 
upper part of the seed of B. Morierei , but states that there were suggestions 
of their presence opposite the outer point of each wing of fibres. 
To sum up, the integuments of these three seeds agree in the possession 
1 Berridge, 1911. 
2 In G. scandens the star-like distribution of the fibres at the apex of the outer integument was 
not so striking as in G. africanum. In G. Gnemon , Miss Berridge tells me that she was also able to 
make out the star-like distribution, but no lignification had occurred. 
3 In G. africanum it is only in the extreme apex that the number of angles is reduced to five ; 
lower down the seed these increase in number. 
