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24 ME. A. C. SEWAKD ON CTCADEOIDEA GXGANTEA. .Feb. 1.897,-
Passing to the apex of the trunk, we find that the leaf-bases become
smaller in size (PI. II. fig. 1), and finally at the extreme tip there is a
conical bud surrounded by several long and narrow bud-scales (fig. 3).
Covering the apex of the bud there is an irregularly-shaped cap of
whitish colour, of which the surface is marked by numerous wavy
lines suggestive of fine scaly or hair-like structures. The bud has
a height of about 3 or 4 cm., and the scale-leaves which are best seen
are about 1*5 cm. long and 6 mm. broad. The appearance of this
terminal bud is shown in PI. I., and more clearly in PI. II. fig. 1,
and in fig. 3. The lighter-coloured cap gives a flat-topped appear-
ing. 3. — Apical bud of Cycadeoidea gigantea, sp. nov.
V\
ance to the bud, and hides the tips of the uppermost scale-leaves

the form of the scales is, however, clearly seen in the lower portion
of the bud. It is important to note that the stem at the base of
the bud is almost circular in outline, thus confirming the opinion
that the flattened appearance shown in fig. 2 (p. 23) is in great
measure due to crushing. In the neighbourhood of the stem-apex
the surface-features are imperfectly preserved, but the leaf-bases are
distinctly visible in many places, and their gradual increase in size
as we pass down the stem is easily recognized.
The material of which the specimen consists is highly siliceous

as shown in fig. 2, the central portion exhibits no trace of plant-
structure, and is composed of cherty rock, while at the periphery
the basal portion of the petioles and the interpetiolar substance are
more or less clearly seen, and are represented in the sketch by
radial lines extending inward a short distance (4 to 5 cm.) from the
surface. There are no traces on the stem of any large lateral buds
such as form so striking a feature in some fossil Cycadean plants,
as, for example, in Bennettites Gibsonianns, Carr., and in some of
the large specimens from North America and Italy. 1 An example
figured by McBride, 2 from Dakota, shows a number of lateral shoots
1 Capellini & Solras-Laubach, ' Tronchi di Bennettitee,' Mem. Eeal. Accad.
Sci. Istit. Bologna, .5., vol. ii. 1892, p. 3.
2 ' The American Geologist,' vol. xii. (1893) p. 248, pi.