Page:A Voyage to Terra Australis Volume 2.djvu/567

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Natural Orders.]
APPENDIX.
553

North Asia, and lastly in the South of Europe, where, however, only two species have been observed, namely, Anagyris fœtida, and Cercis Siliquastrum; but the latter having a straight Embryo and a habit approaching to that of Bauhinia, rather belongs to Lomentaceæ.

Among the Diadelphous genera of Terra Australia the most remarkable in habit and structure, namely Platylobium, Bossiæa, Hovea, Scottia, and Kennedia, are found chiefly in the principal parallel and higher latitudes; within the tropic the greater part of these cease to exist, and most of the genera which there occur are common to other countries, especially India.

ATHEROSPERMEÆ.[1] Jussieu in his excellent memoir on Monimieæ[2] has referred Pavonia of Ruiz and Pavon and Atherosperma of Labillardiere to that order, from the other genera of which, namely, Ambora, Monimia, and Ruiza, they appear to me very different, not only in the insertion of the seed, in the texture of the albumen, and relative size of the Embryo, but in having antheræ similar to those of Laurinæ. I separate them therefore into a distinct family with the name of Atherospermeæ. The propriety of this separation is confirmed by the discovery of two New Holland plants, evidently belonging to this family, but which have hermaphrodite flowers; a structure not likely to occur in Monimieæ, in which what has been termed calyx is more properly an involucrum.

The place of Atherospermeæ in the natural series is not very easily determined. It is singular that differing so widely as they certainly do in most parts of their structure from Laurinæ they should notwithstanding agree with them, in the œconomy of their Antheræ, and very remarkably with some of them in their sensible qualities. Of the three Australian plants of this order
  1. Atherospermeæ. Flores diclines vel hermaphroditi. Calyx monophyllus, limbo diviso: lacinis sæpe duplici serie, interioribus omnibusve semipetaloideis: Squamulæ faucis in femineis et hermaphroditis. Corolla nulla. Stamina in masculis floribus numerosa, fundo calycis inserta, squamulis aucta; in hermaphroditis pauciora, fauce imposita: Antheræ adnatæ, biloculares, loculis valvula longitudinali a basi ad apicem dehiscenti. Ovaria uno plura, sæpius indefinita, monosperma, ovulo erecto: Styli simplices, nunc laterales v. basilares: Stigmata indivisa. Pericarpia clausa seminiformia, stylis persistentibus plumosis aristata, tubo aucto calycis inclusa. Embryo erectus brevis, in basi albuminis carnosi mollis.
    Arbores. Folia opposita simplicia exstipulata. Pedunculi axillares, uniflori.
  2. Annales du museum, 14, p. 116.