6 
CONTRIBUTIONS TO BOTANY. 
being 3-celled at base and unilocular at summit, but they differ 
in their imbricated calyx and corolla, distinct stamens, the pa- 
rietal placentation of the ovarium, and their remarkably stipulate 
leaves. Luxembergia however is placed by M. Planchon, with 
much reason, among the Ochnacece. 
The Olacacete present many strong points of resemblance ; for 
we have there, as in the genus under consideration, a small calyx 
with minute teeth, equal in number to the petals, which are ge- 
nerally four in number, often linear, of thickened texture, and 
valvate in aestivation ; they have also free appendages of various 
forms alternating with the stamens ; these last-mentioned organs 
are frequently monadelphous at base ; they have an ovarium 
wholly superior in regard to the external calyx, often stipitate, 
and sometimes presenting two suspended o\Tiles ; the inflores- 
cence accords, and the pedicels have deciduous bracts at their 
base ; and the leaves are alternate with similar venation. Added 
to these, it appears that in Aptandra the pedicel lengthens and 
the calyx enlarges with the growth of the ovarium after impreg- 
nation, as in Heisteria, and the resemblance in size and shape of 
its flowers to those of Gomphandra is very remarkable. But on 
the other hand, in Olacacets, the appendages are evidently sterile 
stamens, and in no degree partake of the nature and position of 
the petaloid scales of Aptandra ; the stamens are very differently 
constructed, the filaments are always separated from each other, 
often indeed more or less slightly agglutinated to the corolla, 
the bilobed anthers are distinct and introrse, and never open by 
reflected valves, and the structure of the pollen is very different ; 
the fully developed disk, that generally fonns so striking a fea- 
ture in that family, is also wanting in Aptandra. In Olacacea 
we find the flowers generally issuing from bracteated, imbricated 
buds, but in Aptandra we see nothing of this kind. In the in- 
ternal structure of the ovarium of this genus a considerable dif- 
ference is there seen from that existing in most of the genera of 
the Olacacea. In the former the pericai’pial covering is so veiy 
thin and transparent, that by transmitted light its internal stmc- 
ture may easily be distinguished, and the vacuity in the conical 
base of the style is thus seen to be continuous with the cell of 
the ovarium, in the upper part of which the apex of the placenta 
is there seen to be quite free. In most of the genera of the 
OlacacecB the ovarium is half enveloped by, and is partially 
adnate to a fleshy cup-shaped disk, w'hich rises to half the height 
of the ovarium, and which supports the stamens and corolla, 
while the upper moiety of the ovarium is surmounted by a very 
thick fleshy gland ; but no trace of any such hypogynous disk or 
epigynous gland is visible in Aptandra. In the internal struc- 
ture of the ovarium it presents however one of the strongest 
