300 Stapf. — On the Sonerileae of Asia. 
smallest in S'. versicolor (5 mm.), larger in S. pilosula (6 m.), 
and still larger in S. elegans and 5 . travancorica (6-8 mm.). 
IV. Group of S. speciosa. Western Ghats, northwards to 
Mysore. 
This comprises three species distinguished by their robust 
habit, large flowers, and by the venation of the leaves which 
are 3-7-nerved, not 3-7- plo-nerved as in the former group. 
1. S. speciosa , Zenk. Western Ghats from Courtallam to 
Mysore. 
It is a very well-marked species, nearest allied to 5 . 
elegans. 
2. S. grandiflora, R. Br. Nilgherries. 
The most distinct form of the whole series as far as the 
habit is concerned. It is an almost shrubby plant with 
perfectly glabrous, subcoriaceous leaves. 
3. S'. Bensonii , Hook. f. Malabar Ghats (precise locality 
unknown). 
It is nearer to S'. speciosa than to S. grandiflora, but differs 
from all species hitherto mentioned by the number of the 
stamens, both whorls being developed. The great importance 
of this species for the phylogenesis of Sonerila will be 
discussed later on. I wish here only to accent its affinity 
to 6'. speciosa and S'. grandiflora, which is so great that it 
would appear to me quite unnatural to separate it and to 
make it a group by itself. 
The mutual affinities of these first four groups may be ex- 
pressed thus : the group of .S’, zeylanica is linked on one side to 
that of .S'. Gardneri , both exhibiting a parallel divergence in 
their staminal structure, and to that of .S', versicolor in another 
direction, and by means of that group to a still more different 
set, the speciosa - grou p,. which has its most aberrant type in 
.S'. Bensonii. In these two groups, however, no remarkable 
differentiation in the staminal structure exists, this being 
uniform and corresponding with the set of the long anthers 
in group I and group II. All the species of these four 
groups are limited to Ceylon and the Southern half of the 
