490 MR. C. H. WRIGHT ON THE GENUS STEMONA. 
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On the genus Stemona, Lour. By C. H. Wricut, Assistant in 
the Herbarium, Royal Gardens, Kew. (Communicated by 
W.'T. Tusezron Dyer, C.M.G., C.LE., F.R.S., F.L.S.) 
[Read 2nd April, 1896.] 
Tue genus Stemona was founded in 1790 by Loureiro in his 
Flora Cochinchinensis, p. 404, where he describes a single 
species, S. tuberosa. Five years later Banks described the 
same plant in Roxburgh’s Plants of the Coromandel Coast, 1. 
p. 29, t. 32, also as a new genus with the name of Roxburghia 
gloriosoides, under which name the species was formerly culti- 
vated. This is one of the few monocotyledonous genera with 
tetramerous flowers, and it is remarkable for the great diversity 
presented by its vegetative characters, while its reproductive 
organs vary within limits too narrow to admit of it being split 
up into several genera. 
‘The stamens present the most interesting feature of the 
flower. The very short, often broad, filament is surmounted 
by a very wide connective, which is produced on the postical 
sarface into a keel slightly longer than the two anther cells, 
which it completely separates. Above this the connective is 
produced into a more or less subulate appendage, often several 
times the length of the anther celis, and bears upon its postical 
face two small keels, whose lower edges slightly overlap the 
upper end of the keel previously mentioned. The pollen is of 
a somewhat waxy nature, and that contained in each cell is 
welded into a single mass provided with a caudicle which pro- 
trudes from the apex of the anther cell and joins over the 
upper edge of the lowest keel with the caudicle from the other 
cell, and from this point the two united caudicles are prolonged 
upwards. The masses thus formed resemble those met with in 
the Asclepiadee. The caudicles of the four stamens bend 
inwards and touch, while the prolonged connectives bend 
outwards. The ovary is one-celled, with several erect ovules. 
The seeds are oblong, and contain a small, straight embryo in 
the axis of copious albumen. The spermoderm is sulcate and 
produced into a small apiculus at one end. The faniculus 
often attains a considerable length, and bears, just below the 
seed, a bunch of filamentose or vescicular appendages. 
The form most remote from the generic type is met with in 
S. Grifithiana, Kurz, which is an erect herb, whose leaves are 
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