418 
bamboo and other forms, the habit of creeping into “blanks” in the forest 
and they thus retard what would otherwise be the rapid entrance of tree 
species into such places. Usually, the rattan growth is scattered through 
the forest (see Pl. XV), but often individuals are so densely set (PI. 
XVI) that it is difficult to pass through such a location because of the 
armed flagella which, curving downward, catch the clothing. By oceupy- 
ing space and by increasing the already dense shade, they often prevent 
the germination and development of valuable tree species. With the 
exception of Uay, all the species of Calamus here are mesophytic. 
Other lianas——Other families represented by lianas are the Pandana- 
cee and the Aracee. Characteristic of the former is the genus Preyci- 
netia with the species, /’. luzonensis and FI’. ensifolia. F. luzonensis — 
climbs to the tops of largest trees, the ends of its shoots bend stiffly 
outward and upward and develop closely crowded leaves which give a 
characteristic “pandan” tone to the vegetation. Often species of Ara- 
cee of the genus Pothoidium and Rhaphidophora begin their growth 
semi-epiphytically near the bases of large trees and afterwards climb 
by means of roots; at the same time, positively geotropic roots reach 
to the soil and insure a more constant supply of water to the older plant. 
Dicotyledinous forms present on the river plain are also encountered 
in the forest. Besides the ones already mentioned, Artabotrys cumingi- 
anus, Agelewa wallichii, Strongylodon macrobotrys, Entada scandens, 
Modecca sp., Uvaria sp., and others (see Pl. XIV) may also be present. 
Transition from epiphytes to lianas.—The transition from the epiphyte 
to the liana is best expressed by the genus Ficus of the section Uros- 
tigma. (See Pl. XVII.) The species of this group begin as epiphytes 
on the rough surface of the bark or on other parts of the tree where the 
seeds can find lodgment; here they germinate, the roots eventually reach- 
ing and penetrating the ground. In time there is developed a lattice- 
like growth which envelopes the host, and then, as the parts increase in 
diameter, the plant assumes a tree-like habit which enables it to exist 
independently of its host, which eventually dies. The natives term 
the species of Ficus which have developed this habit “balete,’ which, to 
some extent, species of Schefflera of the Aralacee simulate. Plate XVIII 
shows a seedling of S. venulosa which has developed on soil which 
collected in a knot hole of Pithecolobium acle. Plates XVII, XVIII, 
XIX, and XX depict species of Ficus in several stages of maturity. 
Often from branches of the plant there are developed one or more large 
roots which eventually reach the ground. From the base to the top of 
the mountain species of “balete” are found scattered throughout the 
forest. 
Epiphytes—The epiphytic vegetation in contrast with that of the 
higher altitudes is but poorly developed. Mention has been made already 
of the orchids of the river terrace. The rough limbs of Terminalia 
edulis, which grow in more or less protected places, seem to be a favored 
