308 BALFOUR—NEW SPECIES OF RHODODENDRON. 
may be taken together as forming a sub-series marked by this 
character of the under-leaf indumentum. The brown scales are 
truly discontiguous, having conspicuous bare epidermal areas. 
Let me make quite clear that the area without scales is large, 
hence the scales are as it were dotted at intervals over the surface, 
and that the old leaves must be looked at. The leaves in the 
species of this series vary from elliptic to oblong, and form-differ- 
ences are useful to distinguish between closely related species ; 
for instance, Rh. impeditum has the elliptic type, Rh. scintillans 
the oblong. The flowers in the truss are as a rule few—3-5 in 
Rh. fastigiatum, the largest number, 1 only in Rh. verruculosum. 
Some tint of violet or purple marks the flowers, save in Rh. 
flavidum, where they are yellow. Scales on outside of corolla 
is an excellent differential mark. Three species have this—Rh. 
fastigiatum, Rh. flavidum, Rh. verruculosum. 1 know of no more 
useful mark than this for distinguishing RA. fastigiatum amongst 
like forms. Any plant with more than one flower in the truss 
and with lepidote corolla and that shows discontiguous uniform 
scales below is Rh. fastigiatum. The character will enable 
anyone to separate out this species from others which are 
commonly mixed with it in gardens. The 10 exserted stamens 
and the style longer than the stamens are common marks, 
with the exceptions of 7--8 stamens in Rh. verruculosum and a 
puberulous style shorter than the stamens. in Rh. oreshium. 
Rh. complexum is really not in its natural place here, for it has a 
long tube to the corolla and only 5 stamens which with the 
style are included, and these are foreign to the Lapponicum group. 
KEY TO THE SPECIES. 
1. Corolla lepidote . : 2. 
Corolla elepidote [ ‘ ; ‘ ; 4. 
2. eos yellow ‘ ‘ : ‘ eae 
owers purple tinted : ‘“ . 4. 
. ee ee 1-flowered : , ; : saeeariiieaaiie: 
Inflorescence 3-5-flowered ; . fastigiatum. 
4. Stamens and style included in eorota’ tube . . complexum. 
Stamens and style exserted . ; : 5. 
5. Style hairy, shorter thio sca 2 ‘ : oresbium. 
Style glabrous, longer than stamens . ‘ ‘ : 6. 
6. Leaves elliptic, rounded at each end : - tmpeditum. 
Leaves oblong, narrowed at each end ‘ ; scintillans. 
Of the species named here the following are to my knowledge 
in cultivation :—RA. fastigiatum, Rh. flavidum, Rh. Va attien 
Rh. scintillans. 
