28 
CONTRIBUTIONS TO BOTANY. 
the AquifuliacecE, as it is evident that its ovules are really 
suspended from the normal dissepiment, not parietally attached 
to the wall of an originally solitary carjiel. It will also serve to 
guide us to the true position in the system of Leretia, Pogope- 
tnlum, and the rest of the somewhat extensive group of the Ica- 
cinece, which I shall be able to prove to be quite distinct, in 
many leading and essential characters, from the Olucacea. Rhap- 
tostglum, an anomalous genus of the Aquifoliacece, accords with 
Heisteria in many remarkable points ; they agree in habit and 
inflorescence, both having flowers in aggregated axillary clusters, 
growing out of imbricated buds ; they have also a small 5-toothed 
calyx, a corolla of five petals partly cohering at base, but easily 
separable, with a valvate aestivation, ten stamens, five of which 
are opposite, and five alternate with the petals, and partly ad- 
hering to them, a trilocular depressed and somewhat stipitate 
ovarium, with a single ovule suspended in each cell, a short 
erect style, and a clavate stigma : this close approximation of 
characters is very apparent, but the subsequent development of 
the cal 3 'x is not recorded in Rhapfostgluin, nor is the nature of 
its fruit known. The genus Ptgclwpetnlnm of Bentham also 
agrees with Rhaptostijlum in its principal floral characters, but 
differs in its unilocular ovule with two suspended ovules, a nearly 
constant feature of the Icacinece. From the description of 
Kunth, the three cells of the ovarium are sjnnmetrical, and not 
lateral, as in Pogopetalum •, and as the fact of the evanescence of 
the dissepiments at their summit probably escaped the observa- 
tion of that botanist, we may safely conclude that Rhaptostijlum 
will be found to belong to Olacacece rather than to the tribe of 
the Icacinece, or to the family of the Aquifoliacea. lodina again, 
which has always been referred to the last-mentioned familj', 
really belongs, as I shall be able to show, to the Olacacece : this 
curious genus presents a minute cupshaped bractiform calyx, 
with an entirely free campanular fleshy corolla, half cleft into five 
acute lobes, with a valvate aestivation : a large fleshy cup-shaped 
disk, fixed on a distinct stipitate support within the corolla, sur- 
rounds the ovarium, and upon its margin the stamens are in- 
serted ; five of these are fertile, and placed opposite to the lobes 
of the corolla, the others are alternate, squamiform and petaloid, 
having been hitherto described as petals, but from their position 
they are evidently analogous to the sterile stamens of Agonundra, 
a new genus of Olacacece : the depressed ovarium, partly im- 
mersed in the disk, is unilocular, with two to five ovules 
suspended from a cionosperm, or free central placenta. lodina 
from its habit, with its spinous leaves more resembling those of 
the Holly, might well be supposed to belong to Aciuifoliacece, but 
the aestivation of its eorolla, and the peculiar structure of its 
