556 Ridley . — On Endemism and the Mutation Theory . 
smallest kinds. The forest had been let for timber-cutting and the bigger 
trees bearing most of the Orchids cut out, and a patch of forest which 
shaded the edge of the swamp was destroyed, letting light and heat into the 
swamp. 
The extermination of plants by man is not only effected by plantations 
on a large scale and destruction of the forests. Pulau Tawar is a Malay 
village of some size and antiquity on the Pahang river. On a visit there 
I observed that there were no Rattans ( Calami and Daemonorops ) in the 
neighbourhood, even seedlings, except one species of Daemonorops which 
had no value in the eyes of the Malays. 
The Malays, who are insatiable for Rattans for house use and sale, cut 
the long stems when sufficiently developed, that is to say when they are big 
enough to flower. This constant cutting prevents the plant ever reproducing 
itself, and it is only a matter of a comparatively few years before the Rattans 
are utterly exterminated. The wild tribes, too, search the forests in which 
they live thoroughly for eatable Dioscoreas and Palms, as also for Rattans, 
Rubbers ( Willughbeia ), and destroy the big Dipterocarpns trees by boring 
them for wood-oil. Even if some few plants remain scattered here and 
there, they are apt to die out from want of cross-fertilization. 
The extermination of species by man in the Malay Peninsula has really 
been only extensive within the last fifty years. It is very different in 
Ceylon, a heavily populated island for over 2,000 years. Any one who 
visits the forest country round Anuradjahpura will be struck by the small 
size of the trees covering the area which many centuries ago was a thickly 
populated district. Here are the remains of temples which, with the houses 
of the inhabitants, must have been largely built with timber of the felled 
forests. What trees were they that were used for the beams and wood- 
work of the temples and houses ? The valuable Dipterocarpeae, givinggood 
timbers, are given in Trimen’s Flora as six common, twenty-four rare or rather 
rare, twelve very rare, and four or five apparently extinct. Dr. Trimen points 
out the difficulty of obtaining specimens of these trees, and says our know- 
ledge of the Ceylon species is very imperfect ; but the numbers given above 
are about what one would expect of first-class timbers in a heavily populated 
country where timber of large size had been required for 2,000 years. It is 
now highly probable that these plants had formerly a very much larger 
area of extension. A large proportion of the plants labelled very common 
by Dr. Trimen are introduced weeds, and indeed, when in Peradeniya in 
1888, 1 had to go a very long drive and walk before I got to a hill where the 
real Ceylon flora could be seen. Dr. Willis does not, so far as I can see, 
distinguish between the very common introduced plants and the very 
common indigenous plants. What were the plants on the ground before 
these weeds were introduced ? 
