Le 
IV. On several instances of the Anomalous Development of the Raphe in Seeds, and the 
probable causes of such deviations From the usual course of structure, especially in 
reference to Stemonurus (Urañdra of Thwaites), with some Prefatory Remarks on 
that Genus. By Joun Miers, Esq., F.R.S., F.L.S. $c. 
Read April 15th, 1856. 
IN a recent Number of Hooker’s Journal of Botany (vol. vii. p. 211), Mr. Thwaites has 
recorded a new genus, of which he gives the characters under the name of Urandra. 
This he refers to * Olacacee, tribe Icacine@.” I have read over his description with the 
utmost care, and am obliged to say that I perceive no difference whatever in the cha- 
racters of Urandra, and those I have detailed of Stemonurus, to which genus he confesses 
it is closely allied, differing only in all its flowers being fertile, in its small, not pulvinate, 
stigma, and in the structure of its fruit. The character founded on the constancy of the 
hermaphrodite flowers in the plant which he describes, cannot be considered of the 
smallest generic value, because this circumstance has been shown to exist not only in 
some species of Stemonurus, but in the contiguous genus Platea, in which, although 
some of the plants are unisexual, others are frequently hermaphrodite. I have also 
shown that the stigma in Stemonurus (Gomphandra, Wall.) is small, and not large and 
pulvinate as it had been described, but that it becomes subsequently immersed in the 
epigynous gland which crowns the ovary, a circumstance evidently not observed by 
Mr. Thwaites; and that it is this gland which assumes a pulvinate form on the summit of 
the fruit, and not the stigma, which may always be seen hidden in a small central depres- 
‚sion of the cushion. There remains therefore to be considered only the structure of the 
fruit; and Mr. Thwaites's details of the ovary, fruit and seed in Urandra, closely agree 
with what I have observed in Stemonurus. In this genus, as in all others of the 
Icacinacee, where the ovule is usually unilocular, the cell is always excentrically placed 
on one side of the pistil, the point of suspension of the ovules not being from the summit 
of the cell, but constantly inelined against the side on the line of the displaced axis of the 
ovary: the lobes of the stigma are always two or four, thus showing primé facie that 
the ovary is normally bilocular, and that the two ovules observed in the cell are really 
attached, near its summit, to the dissepiment, which, owing to the abortion of the other 
cell, appears to form the wall of the ovary. I was fortunate enough to meet with the proof 
of this conclusion in a ripe fruit of the closely allied genus Pennantia, where été 
is usually unilocular as in Stemonurus; but in the instance alluded to, the cm 
regularly two-celled, and only one seed was perfected in each cell, the sore c på 
ovule being still visible on the dissepiment at the point of attachment of each seed ; 
iti i ishing vessels proceeding from the base formed 
partition was of thin texture, and the nourishing vessels P bt 
a longitudinal nervure in the line of its axis, extending thence to the point of a 
o 
VOL. XXII. 
