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ON THE PROTEACEHS OE JUSSIEU.

advantage referred to that which he has termed Akenium ;but as I am unwilling in the present paper to adopt any termnot more generally sanctioned and understood than this, Ishall content myself with calling those nuces, which areeither not at all or but slightly compressed and not bor-dered ; and apply the term samara to such as are eithervery much compressed, or with a less remarkable com-pression are surrounded or terminated by a membranaceousborder: that I regard these distinctions however as insome cases of very little importance, may be inferred fromthis, that my genus Leucadendron includes both these kindsof fruit.

The first observation I have to offer on the fruits ofProteacese is, that there is no really bivalvular capsule inthe order; a truth which was not perceived by Gscrtner in35] describing his Banksia dactyloides (the Concilium dac-tyloides of Dr. Smith), and which has equally escapedCavanilles and Labillardiere in their characters of Hakea.Dr. Smith has more cautiously omitted this considerationin his character of that genus, and Professor Schrader hasaccurately described the suture as only existing on oneside: such fruits then are as truly folliculi as those ofGrevillea, Bhopala, or Embothrium; and that the existenceof a distinct placenta is by no means necessary to con-stitute this kind of fruit, is proved even by some genera ofApocineae, to which family this term was first applied.

A circumstance occurs in some species of Persoonia towhich I have met with nothing similar in any other plant:the ovarium in this genus, whether it contain one or twoovula, has never more than one cell; but in several of thetwo-seeded species a cellular substance is after fecundationinterposed between the ovula; and this gradually indurat-ing acquires in the ripe fruit the same consistence as theputamen itself, from whose substance it cannot be distin-guished ; and thus a fruit originally of one cell becomesbilocular: the cells however are not parallel, as in all thosecases where they exist in the unimpregnated ovarium, butdiverge more or less upwards.

In all the seeds of this order there is a very manifest

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