106 MR. W. B. HEMSLEY ON TWO SMALL 
comparatively little is known of the flora of Central Asia, little 
reliance should be placed on the figures I have to offer. So 
far as our present knowledge goes, 27 of the species, excluding 
the undetermined ones, which may or may not be new, are 
peculiar to Tibet; 18 are common to Tibet and the Himalayas; 
22 extend eastward to Mongolia or China; 20 have a westward 
extension to Yarkand, Afghanistan, or the Caucasus, and a few of 
them even to Europe; whilst 14 are found all round the Northern 
Hemisphere, and two or three extend into the Southern. 
With regard to the colours of the flowers of the plants inhabit- 
ing this elevated region, Mr. Thorold describes the colours of the 
flowers of all the plants collected, but not always in such a way as 
to lead to an easy classification. Leaving the grasses and sedges 
and a few other plants having quite inconspicuous green or 
yellowish flowers out of the question, I find that flowers with 
some infusion of red predominate. They are variously qualified 
as pinkish, purplish, and so on; but altogether they constitute 
at least 25 per cent. of the collection. Nevertheless, a deep 
intense red would appear to be very rare. Sedum tibeticum is 
perbaps the only plant having fully red flowers. Apart from 
grasses and sedges, in which there is more or less yellow, 25 
species are described as having yellow flowers. Thirteen have blue 
flowers, and some of them of the deepest hue, and one is described 
as violet. Finally, there are fifteen indicated as white. Itis pro- 
bable, however, that colour has now very little importance in this 
alpine flora, which is apparently the remains of a former richer 
vegetation. Insect life, according to Captain Bower, is scarce, 
though butterflies were seen up to an altitude of 17,600 feet. 
I have not had time to study and consider such biological 
evidence as dried plants offer ; but it is clear that some of the 
perennials produce seed in abundance; and such monocarpic or 
annual plants as the Gentians maintain their place in the flora by 
sexual reproduction only. But apart from the evidently mono- 
carpic plants, of which there may be about a dozen in the collec- 
tion, there is no doubt that almost all of them are produced from 
seed, Indeed, with the exception of a very few found near streams 
or in marshy situations, none of the plants increase or spread by 
vegetative propagation. 1 should judge that the ground is no- 
where matted with vegetation, so that there is practically no 
struggle, as between plant and plant, for existence ; and survival is 
largely due to seminal productiveness. No doubt such plants 
as Saussurea glanduligera, Allium senescens, and many other of 
