found by Adanson at Senegal, and has moreover remarked that their ovarium coheres with the tube of the calyx. In that species most common at Sierra Leone, and which is probably one of those examined by M. de Jussien, the ovarium itself is certainly free, its pedicellus, however, as in the greater part of the genera of this order and several of Cæsalpineæ, firmly cohering with the calyx, may account for the statement referred to. I am not, indeed, acquainted with any instance among Dicotyledonous plants of cohesion between a simple ovarium, which I consider that of Chrysobalaneæ to be, and the tube of the calyx.
The complete septum between the two ovula of Parinarium, existing before fecundation, is a peculiar structure in a simple ovarium; though in some degree analogous to the moveable dessepiment of Banksia and Dryandra, and to the complete, but less regular, division of the cavity that takes place after fecundation in some species of Persoonia.[1]
MELASTOMACEÆ. Four plants only of this order occur in the collection.
The first is a species of Tristemma, very nearly related to T. hirtum of M. de Beauvois.[2]
435] The second is perhaps not distinct from Melastoma decumbens, of the same author.[3]
The third and fourth are new species referable to Rhexia, as characterised by Ventenat,[4] though not to that genus as established by Linnæus; and in some respects differing from the species that have been since added to it, all of which are natives of America.
In the original species of Tristemma[5] there are, in the upper part of the tube of the calyx, two circular ciliated membranous processes, from which the name of the genus is derived; the limb of the calyx itself being considered as constituting the third circle. The two circular membranes are also represented as complete in T. hirtum.
But in the species from Congo, which may be named T.
