FLORA NIGRITIANA. 377 
The remaining West Tropical African Loranthi are L. cupu- 
latus, DC., and L. dodoneefolius, DC., from Senegal, L. Thon- 
nngii, DC., from Guinea, and L. sessilifolius, Beauv., from Oware. 
lt is perhaps the only extensive geographical region, especially 
in warm climates, from which no species of Viscum appears to 
have as yet been brought. ` 
LXIV. RUBIACEZ. 
This large Order, so natural and well defined, and yet so diversi- 
fied in detail, is very abundant in Tropical countries, and more 
especially so in West Africa. Its tribes, as successively proposed 
by De Candolle, Jussieu and A. Richard, and finally adopted in 
the Prodromus, are generally easy of determination, but in some 
of the details perhaps too artificial, and a few slight changes 
and" transpositions might render them more conformable to 
hature, without interfering with their practical utility. Too 
much reliance has perhaps been placed on the number of car- 
Pellary parts, and not enough on placentation (insertion of 
ovules), which, with the estivation of the corolla, might in 
many instances better serve, both for the definition and for the 
8rouping of genera. The Nauclee, well marked by their in- 
florescence and seeds, form an excellent tribe, if made to 
include Sarcocephalus, Anthocephalus and Cephalanthus.* In 
the Cinchonew there is little to alter; although the line of de- 
marcation between them and the Rondeletiee is at present very 
ill defined. The remainder of the many-ovuled tribes require 
‘ome re-arrangement. The two-celled genera often present a 
third cell, and the many-celled are not unfrequently reduced 
to two. Gardenia itself has not the characters assigned to the 
* The seeds of Cephalanthus, although solitary in each cell, are inserted 
on a pendulous placenta, as in Stephegyne, and have, like the rest of 
Nawcleg, a wing-like expansion at their apex, although it be so small as 
to have escaped the notice of most botanists. It appears to me also, 
that in the young ovary there are a few additional minute abortive ovules, 
but of that I do not feel certain. 
, 
ase 
