Obs. Exemplaria omnia foliis destituta, sed illorum cicatrices ni fallor obviæ.
[94]In a work published in 1810, the following passage, which has some relation to this subject, occurs. “Capsulas omnes pluriloculares e totidem thecis conferruminatas esse, diversas solum modis gradibusque variis cohæsionis et solubilitatis partium judico.”—(Prodr. Flor. Nov. Holl. 1. p. 558.) This opinion, however, respecting the formation of multilocular ovaria, might be held, without necessarily leading to the theory in question of the composition of the fruit in Cruciferæ, which I first distinctly stated in an Essay on Compositæ, read before the Linnean Society in February 1816, and printed in the 12th volume of their Transactions, published in 1818. In this volume (p. 89), I observe that “I consider the pistillum of all phænogamous plants to be formed on the same plan, of which a polyspermous legumen, or folliculus, whose seeds are disposed in a double series, may be taken as the type. A circular series of these pistilla disposed round an imaginary axis, and whose number corresponds with that of the calyx or corolla, enters into my notion of a flower complete in all its parts. But from this type, and number of pistilla, many deviations take place, arising either from the abstraction of part of the complete series of organs, from their confluence, or from both these causes united, with consequent abortions and obliterations of parts in almost every degree. According to this hypothesis, the ovarium of a syngenesious plant is composed of two confluent ovaria, a structure in some degree indicated externally by the division of the style, and internally by the two cords (previously described), which I consider as occupying the place of two parietal placentæ, each of these being made up of two confluent chordulæ, belonging to different parts of the compound organ.”
In endeavouring to support this hypothesis by referring to certain natural families, in which degradations, as I have termed them, are found, from the assumed perfect pistillum to a structure equally simple with that of Compositæ, and after noticing those occurring in Goodenoviæ, I add, “The natural order Cruciferæ exhibits also obliterations more obviously analogous to those assumed as taking place in syngenesious plants; namely, from a bilocular ovarium with two polyspermous parietal placentæ, which is the usual structure of the order, to that of Isatis, where a single ovulum is pendulous from the apex of the unilocular ovarium; and, lastly, in the genus Bocconia, in the original species of which (B. frutescens), the insertion of the single erect ovulum has the same relation to its parietal placentæ, as that of Compositæ has to its filiform cords, a second species (B. cordata) exists, in which these placentæ are polyspermous.”
From this quotation it is, I think, evident, that in 1818 I had published, in my Essay on Compositæ, the same opinion, relative to the structure of the pistillum of Cruciferæ, which has since been proposed, but without reference to that essay, by M. de Candolle, in the second volume of his “Systema Naturale;” and I am not aware that when the essay referred to appeared, a similar opinion had been advanced by M. de Candolle himself, or by any other author; either directly stated of this family in particular, or deducible from any general theory of the type or formation of the pistillum. I am persuaded, however, that neither M. de Candolle, when he published his Systema, nor M. Mirbel, who has very recently adverted to this subject, could have been acquainted with the passage above quoted. This, indeed, admits of a kind of proof; for if they had been aware of the concluding part of the quotation, the former author would probably not have supposed that all the species referred to Bocconia were monospermous, (Syst. Nat. 2. p. 89); nor the latter that they were all polyspermous. (Mirbel in Ann. des Scien. Nat. 6. p. 267). Respecting Bocconia cordata, though it is so closely allied to Bocconia as to afford an excellent argument in favour of the hypothesis in question, it is still sufficiently different, especially in its polyspermous ovarium, to constitute a distinct genus, to which I have given the name (Macleaya cordata) of my much valued friend, Alexander Macleay, Esq. Secretary to the Colony of New South Wales, whose merits as a general naturalist, a profound entomologist, and a practical botanist, are well known.
OUDNEYA.
Char. Gen. Calyx clausus, basi bisaccatus. Filamenta distincta, edentula. Stigmata connata apicibus distinctis. Siliqua sessilis linearis rostrata, valvis planis uninerviis, funiculis adnatis, septo avenio areolarum parietibus subparallelis. Semina uniseriata. Cotyledones accumbentes.
Suffrutex (O. Africana nob. Hesperis nitens, Viv. lib. p. 38. tab. 5. f. 3.) glaberrimus, ramosus. Folia integerrima sessilia avenia, inferiora obovata, superiora sublinearia. Racemi terminales, ebracteati. Flores mediocris magnitudinis, petalorum laminis obovatis venosis.
Obs. Oudneya ab Arabidi differt stigmatis forma, siliquæ rostro, et dissepimenti areolarum figura. Parrya ad quam genus nostrum accedit diversa est dissepimento binervi venoso! calyce haud clauso, siliquæ forma, et seminibus biseriatis testa corrugata.
[96]Tuckey’s Congo, p. 469.