CONTRIBUTIONS TO BOTANY. 
49 
no such replum becomes manifested, as might be expected ; nor 
does it exist among other genera of the Catalpece, the Incarvillea, 
or the Eccremocarpea. This replum, which results from the 
union of the adjacent midribs of the conjoined carpels, though 
simple in Pithecoctenium and Amphilophiuin, splits into two in 
most of the genera. 
In the second subtribe, the Catalpece, the seeds are not affixed 
near the edges of the valves, as in the preceding group, but close 
to a line down their middle, where they are attached to the margins 
of the narrow transverse dissepiment •, the latter is at first united 
to the valves, but it afterwards separates from them, bearing upon 
each face a single series of seeds placed alternately on the right 
and left. The same occurs in Argylia, where the seeds are 
attached in that manner — not along its median line, as in- 
correctly represented in Endlicber^s ‘ Iconographia,’ tab. 71. It 
sometimes happens in this group that a septiform extension of 
the dissepiment takes place nearly across the cellular spaces, so 
that the capsule becomes apparently 4-celled ; this occurs in 
Sparattosperma, Spathodea, and Heterophragma, where the cruci- 
form dissepiments thus formed are greatly thickened, and occupy 
nearly the whole capacity of the valvular spaces. It is well to 
observe that in these cases the two longer arms of the cruciform 
dissepiment terminate at the sutural commissures of the capsule, 
the two shorter ones in the middle of the valves, and that the 
seeds are borne by the latter ; the ovary, at an early stage, is 
bilocular, when the dissepiment, which is transverse, appears 
much swollen in the axis, where it is not ovuligerous, but the 
ovules are affixed on each side of the axial line : it is this barren 
axial portion that subsequently extends in a cruciform direction, 
ultimately reaching the commissures of the valves. These indi- 
cations are of use as leading to a knowledge of the normal 
structure. In Stereospermum a curious but analogous increment 
takes place : the ovary is 2-locular, with a thin dissepiment, and 
with numerous ovules remotely placed in distinct series ; the 
capsule is cylindrical, very elongated, 2-valved, the central space 
being now filled up with a solid plug of a cork-like substance, 
in transversely articulated, separable, vertebra-like sections, in 
each of which a single seed is imbedded, attached by its hilum 
to the bottom of its foveolar nest, with its two wings extend- 
ing upwards and downwards rectangularly along the inner 
face of the valves ; these seminiferous cavities are placed alter- 
nately in the middle of the four quarters, indicated by four nar- 
row longitudinal cicatrices that run down the entire plug, show- 
ing the lines of its attachment to the middle of the two valves, 
and where it has touched their sutural margins. It would seem 
that a very analogous structure exists in Parmentiera. 
VOL. II. H 
