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low and massive, the formation of wood is greatly emphasized, 
the leaves are thicker and much lessened in numbers, the root 
system is diminished and the branches become knotty and irregu- 
lar, as is often seen in the Alps. Different kinds of Rhododendrons 
and Agapetes, which lower down grew only on trees, as epiphytes, 
change their habit and are found growing on the ground in great 
numbers. Mosses and Lichens are covering the scraggy trees. 
As one goes still higher the trees lessen into low matted bushes, 
which cover the highest points of the mountain peaks. This last 
formation on the summit, which may be compared with the alpine 
savannas, and is about 8,000 feet high, differs much more from the 
lower zones of vegetation on the same mountain, than these alpine 
savannas do from the lower wooded regions of the Alps, although 
on the highest points of the mountains of Java snow is unknown 
and the temperature is for the whole year favorable to plant 
developemnt. 
The peculiarity of the alpine flora is not due to the low tem- 
perature to which it is exposed, but to protective characters, devel- 
oped in order to shield it against a too rapid transpiration. The 
habit of species from widely separated families is here the same. 
The xerophyllous character of the alpine flora of Java finds 
its expression not alone in physiological characteristics, or in the 
presence of Australian forms (Leucopogon, Coprosoma,) or in the 
lack of Phanerogams and other common characters, but in the 
most striking microscopic changes in the anatomy of the parts, 
all looking toward the conservation of moisture. 
Plants with such characters generally lose them when cultiva- 
ted for a time lower down in the valleys. 
y The peculiarities of our alpine flora, such as the gnarly growths, 
| /thickening of leaves, tomentose coverings, &c., have up to the 
| present time been considered as adaptations to the low winter 
: { temperature, and the pressure of the snow. These characters are 
' found, however, on the mountains of Java, in a nearly constant 
summer temperature. I do not hesitate to say that these condi- 
tions, both in the Alps and in Java are referable to one and the 
same cause, i.e.: the greater transpiration caused by less dense 
atmosphere and increased insolation, these conditions rendering 
it more difficult for the plant to provide itself with the necessary 
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