90 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
small, dry Selaginella that here covers all the shelves of the cliffs. 
It has corrugated leaves of bright green, and the flower, so far as 
I could judge from one glimpse of a lingering bloom in early June, 
is pretty and spidery and pink, suggesting a gigantic Bletia, 
carried solitary on a stem of 4 inches — not more than one, it seems 
(and not always that), being produced from each small tuft of 
foliage. A seed-pod has been sent, and also a few pseudo-bulbs, 
collected by a coolie striding barefoot along the face of the 
boulder, as a fly walks lightly along the ceiling. I doubt if it 
will yet be available for distribution. 
Polemonium sp. (F 141) is general up the border, in all characteristic 
Polemonium-places, in river-banks and shingles of the lower 
alpine region, and in and out of the light alpine glades and wood- 
land. It is probably only the tanguticum variety of ubiquitous 
P. coeruleum, but is very much more graceful than the type, with 
loose and scattered showers of blossom on stems of 12-24 inches, 
from early summer onwards. Only a small pinch of seed was 
after all collected, from high in the Siku gorge ; so that F 141 
will probably not be distributed till the resulting plants of this 
have next season yielded their abundant crop. 
Polygonatum sp. (F 274) (? P. roseum) is a dear little fine-leaved 
whorled Solomon's Seal of 4 inches or so, that freely spreads into 
carpets of its larch-like shoots, in the opener alpine places and 
scant turf round the base and ledges of rock-ribs on Thunder- 
crown &c, beset with starry flowers of mauve-pink in June, which 
are followed in autumn by berries of brilliant glowing blood-colour. 
Potentilla F 188 is P. davurica with its fruticosa-Veitchii types, of 
which there are now so many in cultivation. The pure white P. 
Veitchii is abundant all over the foothills of the Siku Alps, &c, 
and only towards the highest limit, in the turf at 12,000 feet, does 
it seem to pass into a yellow form. At least, and until closer inves- 
tigation decides differently, I am inclined to assume that all this 
large range of white-golden fruticosa Potentillas belong in reality 
to one species. As you advance into the Tibetan Alps opposite 
J6-ni the type gets better and the bushes larger. The valley- 
bottoms are filled with masses of deep and brilliant gold, while 
a little higher up the white form comes into fuller possession, and 
the grassy folds of the box-pleated upper alps seem as if mounded 
with masses of snow in August in their couloirs, with banked 
dark forest on one side, and the emerald open lawn on the other, 
in which the Potentillas are profusely peppered in bushes of 
2-3 feet, concealed from sight by their blossom. The deep golden 
type passes into the pure white by innumerable gradations of 
cream, amber, citron, and butter-yellow- — intermediate colour- 
forms (or hybrids) ; seed sent out embraces all these, having 
been collected not only from the snowy and golden extremities 
of the type, but from a little bank in the Mirgo Valley where 
every link between them was in rich abundance and the loveliest 
