CONTRIBUTIONS TO BOTANY. 
251 
useful work, and have been thus led to form many erroneous 
conclusions concerning Mmispermacece. It is scarcely possible 
that this hasty disavowal of valid genera and species can meet 
with general assent or can be maintained when the different 
points of structure are carefully compared. If the method of 
ignoring marked differential features m the floral as well as in 
the carpological structure be adopted in one tribe, as attempted 
here, it ought equally to be applied to the other tribes of the 
family : in such case its many genera, deprived of their precise 
limits, would collapse, and the whole distribution would again 
become involved in endless confusion. In order to avoid this, 
and to preserve one uniform consistency, it appears to me desi- 
rable to maintain Cocculus as a distinct genus of the Platygonea, 
within the limits I have ascribed to it ; otherwise the genus 
Cocculus must disappear, as the Nephroica of Loureiro would 
take its place by right of a priority of many years — or perhaps 
Epibaterium of Forster, which is of still older date. 
In regard to the plea before mentioned, that the form of the 
corolla, even where it assumes uniformly a very peculiar shape, 
is a character too trivial to be entertained, I might cite hundreds 
of instances where that feature forms a leading mark of generic 
distinction ; indeed it has been employed successfully in several 
families by the above-mentioned botanists; and there can be 
no especial reason for discarding it in the Menispermaceac, par- 
ticularly in the instances of Nephroica and Holopeira as distin- 
guished from Cocculus. The carpological structure of Diploclisia 
is unquestionably distinct from that of the last-mentioned 
genus ; its putamen and condyle are constructed upon quite 
a different plan, and its cotyledons and radicle offer very dif- 
ferent proportions ; while the mode of its inflorescence and the 
general aspect of the plants afford the most striking marks of 
distinction. 
The difference in the form of the corolla is so manifest in all 
these four genera, that, in examining the male plants, it is im- 
possible to mistake one genus for another ; but this is not the 
case as regards Pachtjgone, which has a floral structure hardly 
different from Cocculus : the form of the petals and the trimerous 
arrangement of parts are alike in both genera, the only dif- 
ference being that in the former the outer series of bracteiform 
sepals is generally wanting. It is chiefly in the female plant, 
and the structure of the putamen and seed, that the two genera 
become utterly irreconcileable. 
The fruit of Cocculus is well distinguished : the putamen is 
osseous, reniformly globular, slightly compressed, with a pecu- 
liar grooved surface, and has a large excentric condyle, round 
which the lunate or nearly cyclical cell extends; the con- 
2 K 2 
