Page:Miscellaneousbot02brow.djvu/287

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OF PLANTS CALLED COMPOSITE. .^71

I conclude they are not absolutely wanting, but that their connexion with the parietes is still more intimate.

These cords may be supposed to consist either solely of the vessels through which the ovulum is fcecundated, or to contain also the remains or indications of a system of nourishing vessels, or chorda? pistillares, the position of which points out the true nature of the ovarium in this class, or the relation it has to the apparently less simple ovarium of other families. I am inclined to adopt the latter supposition. In order, however, to be understood on this subject, it is necessary to premise that I consider the pistillum or female organ of all phaenogamous plants to be formed on the same plan, of which a polyspermons 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 parts of the calyx bk> or corolla, enters into my notion of a flower complete in all its parts.

But from this type and number of pistilla many devia- tions 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. Ac- cording to this hypothesis, the ovarium of a syngenesious plant is composed of two confluent ovaria ; a structure which is in some degree indicated externally by the division of the style, and internally by the two cords which I con- sider as occupying the place of two parietal placentas, each of these being made up of two confluent chord iilse, be- longing to different parts of the compound organ. I am well aware how very paradoxical such an hypothesis must seem, especially when applied to a structure apparently so simple as that of the ovarium of Composite ; and I there- fore regret that I am not yet fully prepared to bring for- ward in its support a series of facts already in my pos- session, consisting of deviations from the usual structure of organs, and particularly of instances of stamina changed into pistilla,

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