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ON THE SEXUAL ORGANS OF THE CYCADACE^. 69
1. In Cycas the vascular bundles of tlie carpophyll penetrate both
the barren leaf-segment and the ovules in the same way (Plate XCI.
fig. 1, C. remluta).
2. The place where a leaf- segment should be developed is occupied
by an ovule.*
3. The surface of the ovule is continuous with that of the carpophyll,
and has the appearance of a lateral expansion of it. The same epi-
dermis covers both.f
4. The leaf-segments of the sterile part are not entirely flat, but
more or less swollen and cylindrical, which is an approach to the form
of an ovule. This approach it is true is very slight, and the compari-
son between the hardened points of the segments and the hard sum-
mits of the ovules may also seenn too forced. Tliis comparison, how-
ever, adds greater value to a monstrous development of the carpo-
phylls of Cycas Rumphii, which I have previously studied. In many of
them all the ovules were replaced by long leaf-segments. J A carpo-
phyll of the same flower, however, exhibited some ovules, but one of
the sterile segments immediately succeeding the ovules was much more
swollen than the others, and became hollow in its upper part.§ More-
over it was evident by making a section that the vascular bundle did
not remain simply central, but divided a little above the base into
several branches placed all round the axis, and not in the axis itself.
All the other carpophylls exhibited deviations more or less distinct in
the same direction, and I was mistaken in regarding these carpels as
normal, and characteristic of one particular species. Connecting forms
have since convinced me that it must be referred to C. Rumphii (as
that species has been defined by me).
5
.
In all the species of Cycas the ovule is more or less flattened,
being compressed parallel to the plane of the carpophyll, and having
an upper and under surface. This character agrees with the arrange-
ment of the vascular bundles, which are collected together on the two
opposite sides of the external layer of the coat ; when further deve-
lo[)ed, the internal woody layer is' also seen to consist of two halves,
united by lateral sutures, which in C. Rumphii even form two sharp
* See figure of Cycas Rumphii (Lintisea, xxv. tab. ii.).
t See Aualecta Bot. Ind. ii. tab. iy., and figures of the carpophylls of Cycas
generally, especially of C. revohita.
X
Linnaea, ssv. tab. ii. fig. 1.
§ Loc. cit. fig. 3, the first segment to the left, then i-egarded by me as normal.