62 
CONTRIBUTIONS TO BOTANY. 
vening prominent lines, in the case which I observed, were bare 
of ovules, and seemed to arise from the line of junction of the 
thickened sterile margins of the normal carpels, similar to what 
I observed in the ovaria of Kigelia and Schlegelia : at first sight 
these seem to have four hues of placentation ; but a more careful 
observation shows the presence of two only. If this view of the 
structure of the ovary in the Crescentiacea be correct, it will be 
represented as in fig. 16, that is to say, of two carpels pjg, 15 . 
placed face to face, which are placentiferous on their 
midribs and conjoined by their sterile margins, a 
structure that will be seen to correspond with the 
Eccremocarpea (fig. 14), difiFering only in the greater 
thickening of the margins of the carpels. It remains to 
be ascertained whether the pulp of the fruit in these genera results 
from a secretion formed at the internal surface of the ovary, or 
whether it arises from the existence of an arillus round each 
seed : if the latter be the case, as is very probable, it would 
offer a good discriminating character between the Crescentiacece 
and BignoniacecB ; for no trace of any arillus has yet been ob- 
served in the latter family ; otherwise there is little real distinc- 
tion between the two orders. The floral characters in all the 
Crescentiacece are similar to those of the Bignoniacece ; and there 
is no essential difference in the structure of their exalbuminous 
seeds, for it has been shown that the presence or absence of a mem- 
branaceous wing no longer offers any line of distinction between 
the two families. Setting aside the yet uncertain question of an 
arillus, the claims of the Crescentiacece to an ordinal rank are 
feeble, being reduced simply to the presence of pulp and the 
indehiscence of the fruit. If these claims should be considered 
of insuflBcient value, this small group, without inconsistency, 
might still be retained, after the example of DeCandolle, merely 
as a tribe of the Bignoniacece. 
The group of the CyrtandracecB has been considered by many 
of the most eminent botanists as a tribe of the Gesneriacece, 
among whom are Mr. Robert Brown (PI. Jav. Ear. 105), Prof. 
Endlicher (Gen. PL 716), and Mr. Bentham (Lond. Journ. Bot. 
V. 360). On the other hand. Prof. Bindley (Introd. 283) and 
Prof. DeCandolle (Prodr. ix. 258) regard it as a distinct family, 
moi’e allied to Bignoniacece. It differs from Gesneriacece in its 
perfectly and constantly superior ovary and its exalbuminous 
seeds : it accords with Bignoniacece in the form of its calyx and 
corolla ; in its stamens being often didynamous, when frequently 
only two of them are fertile, as in Catalpa ; in its anthers being 
more or less divaricated at their base, and united at their summit 
by a connective, which forms an apicular excurrent appendage ; 
