Ml'. J. Miera on the genus Salpiglohsis. 29 â– Contributions to the Botany of South America. By John Mters, Esq., F.R.S., E.L.S. ' t-' [Continued from vol. iv. p. 363.] Salpiglossis. Upon a former occasion [huj. op. iii. p. 172) many reasons were adduced to show why the tribe of the Salpiglossidece, as constituted by Mr. Bentham (DC. Prodr. x. 190), could not be maintained, and I proposed to limit that tribe simply to Salpiglossis, Browallia, Leptoglossis, and a new genus Pteroglossis, all being distinguished by their singularly dilated stigma and the peculiar mode of aesti-vation of the corolla. A careful examination of Leptoglossis schwenckioides has since then offered reasons for placing that genus among the Petuniece. The SalpiglossidecB, however, as thus limited, are evidently most intimately allied to the Petuniece, agreeing with them in a somewhat similar form of stigma, the development of their stamens, their capsular fruit, and the very spiral form of the embryo in Salpiglossis, and differing from them only in their didynamous stamens and the aestivation of the corolla. The didynamous arrangement of the stamens does not appear to me to offer a sufficient reason for keeping them in an ordinal point of view apart from the Petuniece, and for retaining them in the Scrophulariacece ; indeed in the Petuniece and Nico-tianece, we find an evident tendency towards a didynamous struc-ture, for one of the stamens is constantly shorter than the others, which are in tvfo pairs, while the anther of the fifth is always somewhat smaller, and frequently almost sterile ; and on the other hand, I have observed occasionally in Salpiglossis a fifth fertile stamen, showing a disposition to return to its normal con-dition ; and 1 have also before me an instance of a flower with three pairs of stamens, varying in length, with a seventh shorter one, the anther of which, though smaller than the others, is fer-tile. The position of the Salpiglossidece in the natural system appears to me therefore manifestly in the family which I propose to call Atropacece, or if considered only as a suborder, Atropinece, according to the arrangement there shown {loc. cit. p. 165). There is little in the genus Salpiglossis that calls for observa-tion ; one peculiar feature however claims attention, the singular form of its pollen-grains : these are comparatively large and rea-dily distinguished under a common lens, each granule consisting of four agglutinated spherical globules similar in form to the simple pollen-grains of most Solanacece and Scrophulariacece: three of these globules are on the same plane, the other being superimposed in the centre, thus forming a sort of rounded tetra-hedron, and they adhere so completely that they cannot be sepa-
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