166 
The Philippine Journal of Science 
1915 
medium, or higher altitudes, undescribed forms will continue to 
be found in large or fairly large numbers, for many years to 
come. 
The number of undescribed forms that are appearing in current 
collections is surprisingly great. Individual collections still con- 
tinue to be received in which new species comprise from 10 to 
20, or in some cases, even 25 per cent. Very many years of 
work are necessary before we shall know even approximately the 
total number of species growing in the Philippines. 
Most botanists do not realize the urgent need of an early and 
intensive botanical exploration of countries like the Philippines, 
especially those areas now covered by virgin forest. With the 
rapid increase in population immense areas of virgin forest are 
annually being destroyed in the Malay Archipelago, and with 
this destruction of the original vegetation very many species are 
rapidly being exterminated. Within the memory of men now 
living the virgin forest has been destroyed over vefy large parts 
of eastern Negros to prepare the land for the cultivation of sugar 
cane. Only a few decades ago virgin forest occurred at or near 
the coast of eastern Negros, but now the cleared areas extend 
inland for at least 20 miles. When Blanco was writing his Flora 
de Filipinas, some time previous to the year 1837, it is evident 
that that forest extended very close to what is now the town 
of Angat where Blanco then resided; at the present time one 
must journey for many hours from Angat before reaching any 
type of vegetation that approaches the virgin forest in character. 
In our recent attempt to explore Amboina, with a view to re- 
collecting in their original habitats the species figured and 
described by Rumphius, the late Dr. C. B. Robinson found it 
quite impossible to locate a single tree of many of the species 
considered by Rumphius, as much of the original vegetation of 
Amboina had been destroyed since the time of Rumphius. Like- 
wise the greater part of the island of Java, below an altitude 
of about 1,000 meters, has been entirely denuded of its original 
vegetation. As other islands become more densely populated the 
destruction of the original vegetation is accelerated. It is quite 
impossible to estimate how many species of plants have been 
exterminated by the destruction of the original vegetation over 
vast areas in the Malayan region, but the number is undoubtedly 
great. The factors causing this destruction of the virgin forest 
are more active to-day than at any time in the past, and very 
many species characteristic of the Malayan flora must be col- 
lected in the near future or not at all. The destruction of the 
