Ridley —On Endemism and the Mutation Theory. 567 
Now C. inophyllum is a very peculiar tree ; it grows to a large size on 
sea-shores in sand, and its fruits are adapted specially for sea-dispersal. 
The fruit is green, globose, and resinous ; the endocarp is thin and woody ; it 
is adapted by its lightness for sea-dispersal, and its wide distribution is due 
to this. It is easily nibbled through by rats and squirrels which destroy the 
seed, a catastrophe not likely to occur to any extent in its native habitat, 
where these animals are scarce ; besides, owing to the globose form of the 
fruit, on falling from the tree it usually rolls at once down the sloping shore 
into the water and is drifted out of the reach of the animals. In trees in 
the Botanic Gardens at Singapore, however, the seeds were destroyed in 
hundreds by these animals ; in one year, at least, hardly one escaped. The 
fruit, on account perhaps of the resin, and certainly on account of its size, is 
not swallowed by birds or eaten by bats so far as I have seen. The tree 
does not thrive at any distance from the sea, and does not propagate to any 
extent in scrub or thick forest. It is not to the tree’s interest therefore that 
birds or bats should carry its seeds away inland. 
In C. Burmanni we find the fruit is half an inch or little more long 
and bright orange-coloured. This colouring is unusual in Calophyllum , and 
with its size suggests that the plant is bird-dispersed. Most of this class of 
fruit are green or purplish and seem to be dispersed by fruit-bats. C. ino- 
phytlum , being a maritime plant adapted for inhabiting sea-shores, was in all 
probability evolved in the Polynesian islands, and has been distributed by 
sea as far as the Mascarene islands. The head-quarters of the other inland 
Calophyllums is undoubtedly the Malay Archipelago and peninsula. The 
Ceylon flora possesses a considerable element of Malay forest plants ; 
indeed, nearly all the Ceylon Guttiferae have Malay affinities and all the 
genera and some of the actual species are Malayan. All the evidence of 
this order as of others goes to prove a former land connexion with the 
Malayan region. In this case it is clear that the inland Calophyllums may 
have invaded Ceylon by land at a very early date, while C. inophyllum , 
which occurs practically on every sea-coast it could grow on between 
Polynesia and the Mascarene islands, came by sea, perhaps hundreds or 
thousands of years later, and, as the seeds are still commonly to be found 
drifting along in the sea, may be still landing on the Ceylon shores. What 
then is remarkable in finding C. Burmanni and C. inophyllum in the same 
area ? and what bearing has the one on the other ? 
It is unfortunate that Dr. Willis seems to base so many of his arguments 
on statements made in books rather than on observations made in the field ; 
thus he states (Ann. Roy. Bot. Gard., Perad., iv. d) that Ranunculus bulbosus 
differs (vomR. repens mainly in the fact that the former has the sepals reflexed 
and the latter has them spreading ; but surely the bulbous root of one and 
the stoloniferous habit of the other are important differences, not to mention 
differences in the leaves. In vol. iv, p. 69, he gives a study of the tree 
Q q 2 
