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 •ilO ON THE FEMALE FLOWER AND FRUIT OF

found, consistino^ entirelv of a more minute and much less dense cellnlar tissne. On the surface of this embryo I have observed no point marking original attachment, nor any 229] indication of a channel connecting it with the surface of the albumen, in the centre of which it is seated.

In Cytinus^ in which I believe I have at length found ripe fruits, the seeds are extremely minute, and generally retain at their base the bipartite membrane more distinctly observable in the unimpregnated ovulum. To this mem- brane the name of arillus may be given ; but it may also, and, perhaps, with greater probability, be considered the iuiperfect production of the testa or outer membrane.

The seed itself is elliptical, with a slight inequality at top indicating the depression or perforation observable in the ovulum. The single integument of the seed is easily separable from the nucleus, and by moderate pressure splits longitudinally and with great regvdarity into two equal portions ; in texture it is a crustaceous membrane, indis- tinctly reticulate, the areolae, when very highly mag- nified, appearing to be minutely dotted with a semi-opaque centre.

The nucleus, corresponding exactly in size and form with the integument, has its surface also reticulate, but the areolae are not dotted ; and it appears, as far as I can as- certain in so minute a body, to consist of a uniform cellular tissue, very exactly resembling the nucleus of an Orchideous plant.

The result of the comparison now made, and which might be extended to other points of structure <dl Rafjlema, Bruf/mansia, Hydnora and Cyluius, seems to be, that these four genera, notwithstanding several important differences, form a natural family to which the name of Rafflesl\ce^ may be given ; and that this family is again divisible into three tribes or sections :

The first Bajlesiea, consisting of Babesia and Brugman- sia, is distinguishable by the ovarium being either in part or wholly superior to the origin of the calyx, in its composition or internal structure, in the placentation and direction of

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