THE FLORA OF MANILA. 
169 
of botanical literature, and floras of different regions. A knowl- 
edge of the properties of the various species is essential, for 
very many plants, some of which in the case of the Philippines 
are so thoroughly naturalized as to appear truly indigenous, 
have purposely been introduced for deflnite reasons, for food, 
for medicinal purposes, for dyes, for fibers, and for ornamental 
uses. In many cases it can be determined with a reasonable 
degree of certainty whether a certain species has been purposely 
or inadvertently introduced. Finally there must be taken into 
consideration the communication with various other countries 
both in ancient and in modern times, the origins of peoples 
in archipelagos like the Philippines, and their intercourse with 
other peoples. 
Manifestly the aboriginal inhabitants of the Philippines must 
have reached the Archipelago from some other country, and 
it is certain that in the thousands of years that have elapsed 
since man first reached the Islands, very many plants have been 
introduced, some purposely, some inadvertently, by the early 
invaders and their later successors from Malaya. If we exclude 
the abaca plant {Musa textilis Nee) and the various trees yielding 
timbers, gums, and resins, a few palms, some bamboos, the 
rattans, etc., it will be found that practically all the species 
now found in the Archipelago that are of the greatest impor- 
tance in the economy of the native, whether for food, for con- 
diments, for clothing, for dyes, for ornamental purposes, and 
very many for medicinal purposes, have originated outside of 
the Philippines, and have purposely been introduced at one 
time or another. Not a single important food plant or fruit 
tree has originated in the Archipelago, but all have been intro- 
duced. 
While prehistoric trade routes by which plants have been 
brought to the Philippines are not definitely known, still from 
the geographic location of the Archipelago, it would seem that 
communication must have been mostly with other Islands of 
the Malay Archipelago, and to a lesser degree with the Asiatic 
continent. A great many plants of economic importance were 
introduced in prehistoric times, and certainly at the same time 
a considerable number of weeds of cultivation. It is possible 
to determine, with at least a reasonable degree of certainty, 
most of the introduced species that were established or cultivated 
in the Archipelago before the advent of the Europeans. 
With the advent of the Europeans and the consequent in- 
creased communication between the Philippines and neighboring 
