FLOWER OF GNETUM 
155 
considerably even within the same species. Karsten 1 found, almost without 
exception, in G. Gnemon, 11 parastichies each containing 5 — 7 flowers, i.e. 
about 66 flowers at each node. The material now under examination yields 
the following figures : 
Species 
Origin 
Parastichies 
Flowers in 
Parastichy. 
Flowers 
at node 
G. Gnemon 
Singapore 
7 
7 
49 
do. 
Ceylon 
9-15 
6 
— 90 
do. 
Buitenzorg 
10 
5—6 
50 
G. scandens 
Tenasserim 
16—32 
4—6 
60 — 
G. africanum 
Angola 
9 
3—5 
27 - 
G. Buchholzianum 
Cameroons 
12 
3—4 
40 
The number of flowers on a single inflorescence is therefore very large ; in 
G. scandens, for example, the number of nodes is rarely less than 14 and 
frequently as many as 17 ; the number of male flowers formed on the 
inflorescence about 1 inch long may therefore exceed 3000. 
The antherophore remains enclosed in the utricular envelope until the 
pollen grains are almost mature ; it then appears to elongate very rapidly, 
pushing the anthers through the aperture at the summit of the envelope and 
over the edge of the subtending cupule. In this process, as in the last stage 
of the elongation of the androecium of Welwitschia 2 , the starch which is 
present in abundance in the cells of the young antherophore becomes quite 
exhausted. Also the cells which in the early stages are approximately isodia- 
metric, in the fully extruded antherophore are much elongated in the 
direction of the axis of the whole structure, being 8 — 10 times as long as 
broad. When once the antherophore is fully extended the anthers dehisce 
or are so near the point of dehiscence that a very slight pressure is sufficient 
to cause them to open (Fig. 3 A). Sooner or later after dehiscence, the whole 
flower, with the envelope, falls away (Fig. 4). The bared surface is now 
densely covered by hairs and, except for the trunks of the vascular traces 
there is no sign that it has ever borne male flowers (Fig. 4). The incom- 
plete female flowers (G. Gnemon ) appear to reach maturity before the anthers 
of the oldest male flowers dehisce, after which they shew no further increase 
in size. The embryo sac sometimes develops as far as the stage at which 
the sac nuclei become grouped for fusion 3 . In the inflorescence from which 
all or nearly all the male flowers have fallen, the embryo sac of ovules with 
only two envelopes, in all cases examined, had disappeared and was repie- 
sented only by a hole in the nucellus. Complete female flowers which 
frequently occur among them 3 , if pollinated, appear to be fertilised and to 
undergo normal development. 
1 Karsten, l.c. p. 343. 2 cf - Churcb > 1914, p. 143. 
3 Cf. Pearson, 1915. 
