orresponding
surfaces, and together constitute the anomalous dissepiment of the
capsule; the inner membrane of the ovulum consequently forming the outer
coat of the seed.

(*Footnote. Linnean Society Transactions 12 page 149.)

(**Footnote. Ibid.)

The inner membrane of the ovulum, however, in general appears to be of
greater importance as connected with fecundation, than as affording
protection to the nucleus at a more advanced period. For in many cases,
before impregnation, its perforated apex projects beyond the aperture of
the testa, and in some plants puts on the appearance of an obtuse, or
even dilated stigma; while in the ripe seed it is often either entirely
obliterated, or exists only as a thin film, which might readily be
mistaken for the epidermis of a third membrane then frequently
observable.

This third coat is formed by the proper membrane or cuticle of the
Nucleus, from whose substance in the unimpregnated ovulum it is never, I
believe, separable, and at that period is very rarely visible. In the
ripe seed it is indistinguishable from the inner membrane only by its
apex, which is never perforated, is generally acute and more deeply
coloured, or even sphacelated.

The membrane of the nucleus usually constitutes the innermost coat of the
seed. But in a few plants an additional coat, apparently originating in
the inner membrane of Grew, the vesicula colliquamenti or amnios of
Malpighi also exists.

In general the Amnios, after fecundation, gradually enlarges, till at
length it displaces or absorbs the whole substance of the nucleus,
containing in the ripe seed both the embryo and albumen, where the latter
continues to exist. In such cases, however, its proper membrane is
commonly obliterated, and its place supplied either by that of the
nucleus, by the inner membrane of the ovulum, or, where both these are
evanescent, by the testa itself.

In other cases the albumen is formed by a deposition of granular matter
in the cells of the nucleus. In some of these cases the membrane of the
amnios seems to be persistent, forming even in the ripe seed a proper
coat for the embryo, the original attachment of whose radicle to the apex
of this coat may also continue. This, at least, seems to me the most
probable explanation of the structure of true Nymphaeaceae, namely,
Nuphar, Nymphaea, Euryale, Hydropeltis, and Cabomba, notwithstanding
their very remarkable germination, as observed and figured in Nymphaea
and