218 The Philippine Journal of Science isn 
island since the eruption in 1911 indicates that about two-thirds 
of the species which were common before the eruption occur 
on the island at the present time. 
The invasion of Volcano Island by new species has evidently 
taken place at a very rapid rate. However, only thirteen species 
are listed in Table IV as common and widely distributed. This 
indicates that few of the species have found favorable habitats 
of considerable extent and affords additional evidence that the 
slowness of revegetation is due to adverse environmental con- 
ditions rather than to a lack of seeding. 
A large proportion of the species are widely distributed in the 
tropics. Ninety-six, or 33 per cent, are of pantropic distribution ; 
while an additional one hundred fifty, or 51 per cent, are found 
in other parts of the Indo-Malayan region as well as in the Phil- 
ippines. Only forty-six, or 16 per cent, are confined to the 
Philippine archipelago. Most of the species on Volcano Island 
are common and widely distributed in inhabited areas at low 
altitudes in the Philippines. Merrill has shown that in such 
regions the percentage of endemic species is small, being only 
about 12 per cent. In his calculations cultivated as well as 
spontaneous species are considered. The percentage of endem- 
ism among spontaneous species would be somewhat greater. 
The preponderance of widely distributed plants in the cul- 
tivated areas in the Philippines is similar to the condition pre- 
vailing in many tropical countries. The wide distribution of 
these species is due to the fact that many tropical countries 
originally supported tall dense forests, the removal of which, 
produced conditions suitable for plants more xerophytic than 
most of those previously occurring in the region. The artificial 
production of similar habitats in many parts of the tropics has 
made it possible for plants suitable for those habitats to become 
widely distributed, largely through the agency of man, either 
purposely or accidentally. 
Most of the species on Krakatau are also of wide distribution. 
In speaking of those in the interior of the island Ernst says : 
Within their respective distribution-areas they belong to the commonest 
plants and to such as grow indifferently in a great variety of habitats. 
These constituents of the new Krakatau flora owe their occurence in the new 
habitat, as also their wide distribution, chiefly to the efficient adaptation 
of their fruits and seeds to distant transport. 
Merrill, E. D., Notes on the Flora of Manila with special reference to 
the introduced element, Philip. Joum. Sci. 7 (1912) Bot. 145-208. 
■" Ernst, A., The New Flora of the Volcanic Island of Krakatau (1908) 48. 
