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 Rh (like Philydrum and Brunonia ), now that its structure is completely known, to rank as a distinct family which may be called, and which may be placed between Crassulaceæ and Francoaceæ; differing from both in being apetalous, in the valvate æstivation of the perianthium, and in many characters of inferior importance: from Crassulaceæ also in its minute embryo and more copious albumen: and from Francoaceæ in the absence of barren stamina and in the pistilla being monospermous and apparently distinct.

The most striking peculiarity of Cephalotus consists in the conversion of a portion of its radical leaves into Ascidia or pitchers. But as ascidia in all cases are manifestly formed from or belong to leaves, and as the various parts of the flower in Phænogamous plants are now generally regarded as modifications of the same organs, the question is naturally suggested, how far the form and arrangement of the parts of fructification agree in those plants whose leaves are capable of producing ascidia or pitchers. The four principal, and indeed the only genera in which pitchers occur, are Nepenthes, Cephalotus, Sarracenia, and Dischidia, and the few other somewhat analogous cases, consisting of the conversion of bracteæ or floral leaves into open cuculli, are found in Marcgravia and two other genera of the same natural family.

The only thing common to all these plants is, that they are Dicotyledonous.

It may also be remarked, that in those genera in which the Ascidia have an operculum, namely Nepenthes, Cephalotus, and Sarracenia, they exist in every known species of each genus, and the structure of these genera is so peculiar that they form three distinct natural families; while in Dischidia, whose pitchers are formed without opercula, these organs are neither found in every species of the genus, nor in any other genus of the extensive natural order to which it belongs.

The striking resemblance in most points of the Ascidia of