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Alfred Russel Wallace
English Naturalist
1823-1913 A selection from
THE MALAY ARCHIPELIGO
Narrated by Ralph Cosham
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By far the most interesting incident in my visit to Java was a
trip to the summit of the Pangerango and Gedeh mountains; the
former an extinct volcanic cone about 10,000 feet high, the
latter an active crater on a lower portion of the same mountain
range. Tchipanas, about four miles over the Megamendong Pass, is
at the foot of the mountain. A small country house for the
Governor-General and a branch of the Botanic Gardens are situated
here, the keeper of which accommodated me with a bed for a night.
There are many beautiful trees and shrubs planted here, and large
quantities of European vegetables are grown for the Governor-
General's table. By the side of a little torrent that bordered
the garden, quantities of orchids were cultivated, attached to
the trunks of trees, or suspended from the branches, forming an
interesting open air orchid-house. As I intended to stay two or
three nights on the mountain, I engaged two coolies to carry my
baggage, and with my two hunters we started early the next
morning.
The first mile was over open country, which brought us to the
forest that covers the whole mountain from a height of about
5,000 feet. The next mile or two was a tolerably steep ascent
through a grand virgin forest, the trees being of great size, and
the undergrowth consisting of fine herbaceous plants, tree-ferns,
and shrubby vegetation. I was struck by the immense number of
ferns that grew by the side of the road. Their variety seemed
endless, and I was continually stopping to admire some new and
interesting forms. I could now well understand what I had been
told by the gardener, that 300 species had been found on this one
mountain. A little before noon we reached the small plateau of
Tjiburong, at the foot of the steeper part of the mountain, where
there is a plank-house for the accommodation of travellers. Close
by is a picturesque waterfall and a curious cavern, which I had
not time to explore. Continuing our ascent the road became
narrow, rugged and steep, winding zigzag up the cone, which is
covered with irregular masses of rock, and overgrown with a dense
luxuriant but less lofty vegetation. We passed a torrent of water
which is not much lower than the boiling point, and has a most
singular appearance as it foams over its rugged bed, sending up
clouds of steam, and often concealed by the overhanging herbage
of ferns and lycopodia, which here thrive with more luxuriance
than elsewhere.
At about 7,500 feet we came to another hut of open bamboos, at a
place called Kandang Badak, or "Rhinoceros-field," which we were
going to make our temporary abode. Here was a small clearing,
with abundance of tree-ferns and some young plantations of
Cinchona. As there was now a thick mist and drizzling rain, I did
not attempt to go on to the summit that evening, but made two
visits to it during my stay, as well as one to the active crater
of Gedeh. This is a vast semicircular chasm, bounded by black
perpendicular walls of rock, and surrounded by miles of rugged
scoria-covered slopes. The crater itself is not very deep. It
exhibits patches of sulphur and variously-coloured volcanic
products, and emits from several vents continual streams of smoke
and vapour. The extinct cone of Pangerango was to me more
interesting. The summit is an irregular undulating plain with a
low bordering ridge, and one deep lateral chasm. Unfortunately,
there was perpetual mist and rain either above or below us all
the time I was on the mountain; so that I never once saw the
plain below, or had a glimpse of the magnificent view which in
fine weather is to be obtained from its summit. Notwithstanding
this drawback I enjoyed the excursion exceedingly, for it was the
first time I had been high enough on a mountain near the Equator
to watch the change from a tropical to a temperate flora. I will
now briefly sketch these changes as I observed them in Java.
On ascending the mountain, we first meet with temperate forms of
herbaceous plants, so low as 3,000 feet, where strawberries and
violets begin to grow, but the former are tasteless, and the
latter have very small and pale flowers. Weedy composites also
begin to give a European aspect to the wayside herbage. It is
between 2,000 and 5,000 feet that the forests and ravines exhibit
the utmost development of tropical luxuriance and beauty. The
abundance of noble Tree-ferns, sometimes fifty feet high,
contributes greatly to the general effect, since of all the forms
of tropical vegetation they are certainly the most striking and
beautiful. Some of the deep ravines which have been cleared of
large timber are full of them from top to bottom; and where the
road crosses one of these valleys, the view of their feathery
crowns, in varied positions above and below the eye, offers a
spectacle of picturesque beauty never to be forgotten. The
splendid foliage of the broad-leaved Musceae and Zingiberaceae,
with their curious and brilliant flowers; and the elegant and
varied forms of plants allied to Begonia and Melastoma,
continually attract the attention in this region. Filling in the
spaces between the trees and larger plants, on every trunk and
stump and branch, are hosts of Orchids, Ferns and Lycopods, which
wave and hang and intertwine in ever-varying complexity. At about
5,000 feet I first saw horsetails (Equisetum), very like our own
species. At 6,000 feet, raspberries abound, and thence to the
summit of the mountain there are three species of eatable Rubus.
At 7,000 feet Cypresses appear, and the forest trees become
reduced in size, and more covered with mosses and lichens. From
this point upward these rapidly increase, so that the blocks of
rock and scoria that form the mountain slope are completely
hidden in a mossy vegetation. At about 5,000 feet European forms
of plants become abundant. Several species of Honeysuckle, St.
John's-wort, and Guelder-rose abound, and at about 9,000 feet we
first meet with the rare and beautiful Royal Cowslip (Primula
imperialis), which is said to be found nowhere else in the world
but on this solitary mountain summit. It has a tall, stout stem,
sometimes more than three feet high, the root leaves are eighteen
inches long, and it bears several whorls of cowslip-like flowers,
instead of a terminal cluster only. The forest trees, gnarled and
dwarfed to the dimensions of bushes, reach up to the very rim of
the old crater, but do not extend over the hollow on its summit.
Here we find a good deal of open ground, with thickets of shrubby
Artemisias and Gnaphaliums, like our southernwood and cudweed,
but six or eight feet high; while Buttercups, Violets,
Whortleberries, Sow-thistles, Chickweed, white and yellow
Cruciferae Plantain, and annual grasses everywhere abound. Where
there are bushes and shrubs, the St. John's-wort and Honeysuckle
grow abundantly, while the Imperial Cowslip only exhibits its
elegant blossoms under the damp shade of the thickets.
The fact of a vegetation so closely allied to that of Europe
occurring on isolated mountain peaks, in an island south of the
Equator, while all the lowlands for thousands of miles around are
occupied by a flora of a totally different character, is very
extraordinary; and has only recently received an intelligible
explanation. The Peak of Teneriffe, which rises to a greater
height and is much nearer to Europe, contains no such Alpine
flora; neither do the mountains of Bourbon and Mauritius. The
case of the volcanic peaks of Java is therefore somewhat
exceptional, but there are several analogous, if not exactly
parallel cases, that will enable us better to understand in what
way the phenomena may possibly have been brought about.
The higher peaks of the Alps, and even of the Pyrenees, contain a
number of plants absolutely identical with those of Lapland, but
nowhere found in the intervening plains. On the summit of the
White Mountains, in the United States, every plant is identical
with species growing in Labrador. In these cases all ordinary
means of transport fail. Most of the plants have heavy seeds,
which could not possibly be carried such immense distances by the
wind; and the agency of birds in so effectually stocking these
Alpine heights is equally out of the question. The difficulty was
so great, that some naturalists were driven to believe that these
species were all separately created twice over on these distant
peaks. The determination of a recent glacial epoch, however, soon
offered a much more satisfactory solution, and one that is now
universally accepted by men of science. At this period, when the
mountains of Wales were full of glaciers, and the mountainous
parts of Central Europe, and much of America north of the great
lakes, were covered with snow and ice, and had a climate
resembling that of Labrador and Greenland at the present day, an
Arctic flora covered all these regions. As this epoch of cold
passed away, and the snowy mantle of the country, with the
glaciers that descended from every mountain summit, receded up
their slopes and towards the north pole, the plants receded also,
always clinging as now to the margins of the perpetual snow line.
Thus it is that the same species are now found on the summits of
the mountains of temperate Europe and America, and in the barren
north-polar regions.
But there is another set of facts, which help us on another step
towards the case of the Javanese mountain flora. On the higher
slopes of the Himalayas, on the tops of the mountains of Central
India and of Abyssinia, a number of plants occur which, though
not identical with those of European mountains, belong to the
same genera, and are said by botanists to represent them; and
most of these could not exist in the warm intervening plains. Mr.
Darwin believes that this class of facts can be explained in the
same way; for, during the greatest severity of the glacial epoch,
temperate forms of plants will have extended to the confines of
the tropics, and on its departure, will have retreated up these
southern mountains, as well as northward to the plains and hills
of Europe. But in this case, the time elapsed, and the great
change of conditions, have allowed many of these plants to become
so modified that we now consider them to be distinct species. A
variety of other facts of a similar nature have led him to
believe that the depression of temperature was at one time
sufficient to allow a few north-temperate plants to cross the
Equator (by the most elevated routes) and to reach the Antarctic
regions, where they are now found. The evidence on which this
belief rests will be found in the latter part of Chapter II. of
the "Origin of Species"; and, accepting it for the present as an
hypothesis, it enables us to account for the presence of a flora
of European type on the volcanoes of Java. More information about Alfred Russel Wallace from Wikipedia
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