BALFOUR—NEW SPECIES OF RHODODENDRON. 123 
margins and either glandular on the under surface or glandular 
with a thin indumentum of hairs but the indumentum never 
forming a surface concealing the underlying epidermis. Flowers 
either solitary and terminal or in few-flowered (up to 3) umbels, 
the inner large sheathing bracts persisting as a sheath around 
base of the pedicels during flowering. The pedicels always 
glandular or floccose or both. The calyx not large but the lobes 
always distinct. The corolla tubular-campanulate large for the 
plant more or less fleshy crimson of some tint often incom- 
pletely septate at base, glabrous inside and outside. Stamens 
Io subequal; filaments glabrous or puberulous. Disk large 
glabrous or puberulous. Gynaeceum slightly longer than 
stamens shorter than corolla; ovary glandular with long 
stalked glands or tomentose with fasciate floccose ascending 
hairs or showing a combination of these; style glabrous. 
These characters in brief are given not as defining the series 
—we do not know enough about it yet—but merely to indicate 
the run of the development in the members of the series and 
to suggest the whereabouts of the position of these plants 
in the now very large genus Rhododendron. They evidently 
bring Rh. Forrestii and its allies into the vicinity of Rh. san- 
guineum which as is explained elsewhere (see p. 81) hinges 
on to Rh. haematodes, to Rh. floccigerum, and finally to Rh. 
neriifiorum, of known species. The gynaeceum with its 
glandular, floccose, or glandular-floccose ovary and the glabrous 
sty e, the sequence from solitary to few-flowered trusses in 
pubeiseornee, the fleshy more or less campanulate corolla often 
mperfectly septate of strong colour, the gradation of type of 
ndumentum marking these species seem to bring them together 
in closer affinity one with another than with other species. 
For practical working with these rhododendrons the characters 
named are useful in focussing what appear to be relationships 
as we endeavour to fix phyletic groups. 
The following key based upon the indumentum of under- 
leaf surface gives easily observed diagnostic marks of the species 
Within the series centring in-Rh. Forresti :— 
Leaf under-surface deep purple-red. 
Leaf under-surface without hairs, glandular 
Lea . i with — hair-indumentum porphyrophyllum. 
fu 
Leaf under-surface green or glau 
Lea ceaucteaort without’ parte glandular 
repens. 
Leaf paikeetastace with tufted detersile hairs 
ng the vein erastum. 
Leaf under-surface uniformly covered with 
serpens. 
thin brown indumentum 
