connected with the Flora of Guiana. 229 
often above the middle, and then suddenly expanded ; the segments are always 
in a single row, (though imbricate in zstivation,) nearly equal in size, and 5 
in number in the species I have seen, 6, or perhaps more, in some described 
by Bonpland, and the ovary 3- 4- or 5-celled. Of this group I have examined 
S. martinicensis, Linn., S. Ciponima, S. Arechea, L'Hér., Stemmatosiphon platy- 
phyllum, nitens, and uniflorum, Pohl., Symplocos pubescens, Klotsch, and two 
new species described below ; and, judging from Bonpland's figures, I should 
likewise refer to it his Symplocos serrulata and rufescens. 
As a second genus, or at any rate as a distinct section of Symplocos, I 
should propose to restore Linnzeus’s Alstonia, characterized by a more cam- 
panulate corolla, with an inner row of small corolline segments, which may 
perhaps be considered as an outer row of sterile stamina. I have only seen 
one species, the Alstonia theæformis, Linn., and of that I could only dissect 
one imperfect flower, in which the inner row of petals was very irregular, and 
certainly took the place of some of the external stamina. I should associate 
with it Bonpland's Symplocos cernua and coccinea, judging from the figures, 
and perhaps also Symplocos tomentosa, Bonpl., and S. octopetala, Swartz. 
But it would require a re-examination of all these species to determine the 
importance of the inner row of petals as characterizing a section or a 
genus. 
In the third very distinct genus, Hopea, Linn. (not Roxb.), the aspect of the 
flower is very different; the corolla is almost rotate, constantly uniseriate at 
the base, though the divisions be imbricate, and 5- or 6-cleft; the stamina are 
also spreading, their filaments slender, but slightly connected at the base, often 
somewhat pentadelphous, and usually longer than the corolla. I have also 
never found more than three cells to the ovary, (in H. sinica and cratægoides 
there are but two,) and the species appear much more apt to dry yellow than 
in the true Symplocos. I would refer to Hopea, so characterized, H. tinctoria, 
Linn., and the greater number, if not all the Asiatic species. Amongst these 
the S. sinica, Bot. Reg., and S. cratægoides, Hamilt., should form a distinct 
section, as proposed by Don, but characterized by the bilocular ovarium and 
comparatively slender stigmata. There appears also to be a considerable di- 
versity in the fruit, which is pear- or bottle-shaped, and very small in S. spi- 
cata, Roxb., S. polycarpa, Wall., and S. laurina, Wall., small, oblong, and 
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