Chapter VII: Part 7

Among the places on the globe where the temperature falls lowest are
some in northern Asia; and among those where it rises highest are some
in southern Asia. The mean temperature of the north coast of eastern
Siberia is but a few degrees above the zero of Fahrenheit; the lowest
mean temperature anywhere observed is about 4 deg. Fahr., at Melville
Island, north of the American continent. The isothermals of mean
annual temperature lie over northern Asia on curves tolerably regular
in their outline, having their western branches in a somewhat higher
latitude than their eastern; a reduction of 1 deg. of latitude
corresponds approximately--and irrespective of modifications due to
elevation--to a rise of 1/2 deg. Fahr., as far say as 30 deg. N, where
the mean temperature is about 75 deg. Fahr. Farther south the increase
is slower, and the highest mean temperature anywhere attained in
southern Asia is not much above 82 deg. Fahr.

The variations of temperature are very great in Siberia, amounting
near the coast to more than 100 deg. Fahr., between the mean of the
hottest and coldest months, and to still more between the extreme
temperatures of those months. In southern Asia, and particularly near
the sea, the variation between the hottest and coldest monthly means
is very much less, and under the equator it is reduced to about 5 deg.
In Siberia the difference between the means of the hottest and coldest
months is hardly anywhere less than 60 deg. Fahr. On the Sea of Aral
it is 80 deg. Fahr., and at Astrakhan, on the Caspian, more than 50
deg. At Tiflis it is 45 deg. In northern China, at Peking, it is 55
deg., reduced to 30 deg. at Canton, and to 20 deg. at Manila. In
northern India the greatest difference does not exceed 40 deg., and it
falls off to about 15 deg. at Calcutta and to about 10 deg. or 12 deg.
at Bombay and Madras. The temperatures at the head of the Persian Gulf
approximate to those of northern India, and those of Aden to Madras.
At Singapore the range is less than 5 deg., and at Batavia in Java,
and Galle in Ceylon, it is about the same. The extreme temperatures in
Siberia may be considered to lie between 80 deg. and 90 deg. Fahr. for
maxima, and between -40 deg. and -70 deg. Fahr. for minima. The
extreme of heat near the Caspian and Aral Seas rises to nearly 100
deg. Fahr., while that of cold falls to -20 deg. Fahr. or lower.
Compared with these figures, we find in southern Asia 110 deg. or 112
deg. Fahr. as a maximum hardly ever exceeded. The absolute minimum in
northern India, in lat. 30 deg., hardly goes below 32 deg.; at
Calcutta it is about 40 deg., though the thermometer seldom falls to
50 deg. At Madras it rarely falls as low as 65 deg., or at Bombay
below 60 deg. At Singapore and Batavia the thermometer very rarely
falls below 70 deg., or rises above 90 deg. At Aden the minimum is a
few degrees below 70 deg., the maximum not much exceeding 90 deg.

These figures sufficiently indicate the main characteristics of the
air temperatures of Asia. Throughout its northern portion the winter
is long and of extreme severity; and even down to the circle of 35
deg. N. lat., the minimum temperature is almost as low as zero of
Fahrenheit. The summers are hot, though short in the northern
latitudes, the maximum of summer heat being comparatively little less
than that observed in the tropical countries farther south. The
moderating effect of the proximity of the ocean is felt in an
important degree along the southern and eastern parts of Asia, where
the land is broken up into islands or peninsulas. The great elevations
above the sea-level of the central part of Asia, and of the
table-lands of Afghanistan and Persia, tend to exaggerate the winter
cold; while the sterility of the surface, due to the small rainfall
over the same region, operates powerfully in the opposite direction in
increasing the summer heat. In the summer a great accumulation of
solar heat takes place on the dry surface soil, from which it cannot
be released upwards by evaporation, as might be the case were the soil
moist or covered with vegetation, nor can it be readily conveyed away
downwards as happens on the ocean. In the winter similar consequences
ensue, in a negative direction, from the prolonged loss of heat by
radiation in the long and clear nights--an effect which is intensified
wherever the surface is covered with snow, or the air little charged
with vapour. In illustration of the very slow diffusion of heat in the
solid crust of the earth, and as affording a further indication of the
climate of northern Asia, reference may here be made to the frozen
soil of Siberia, in the vicinity of Yakutsk. In this region the earth
is frozen permanently to a depth of more than 380 ft. at which the
temperature is still 5 deg. or 6 deg. Fahr. below the freezing point
of water, the summer heat merely thawing the surface to a depth of
about 3 ft. At a depth of 50 ft. the temperature is about 15 Fahr.
below the freezing point. Under such conditions of the soil, the land,
nevertheless, produces crops of wheat and other grain from fifteen to
forty fold.

The very high summer temperatures of the area north of the tropic of
Cancer are sufficiently accounted for, when compared with those
observed south of the tropic, by the increased length of the day in
the higher latitude, which more than compensates for the loss of heat
due to the smaller mid-day altitude of the sun. The difference between
the heating power of the sun's rays at noon on the 21st of June, in
latitude 20 deg. and in latitude 45 deg., is only about 2%; while the
accumulated heat received during the day, which is lengthened to
15-1/2 hours in the higher latitude, is greater by about 11% than in
the lower latitude, where the day consists only of 13-1/4 hours.

Although the foregoing account of the temperatures of Asia supplies
the main outline of the observed phenomena, a very important modifying
cause, of which more will be said hereafter, comes into operation over
the whole of the tropical region, namely, the periodical summer rains.
These tend very greatly to arrest the increase of the summer heat over
the area where they prevail, and otherwise give it altogether peculiar
characteristics.

Pressure and Winds.

The great summer heat, by expanding the air upwards, disturbs the
level of the planes of equal pressure, and causes an outflow of the
upper strata from the heated area. The winter cold produces an effect
of just an opposite nature, and causes an accumulation of air over the
cold area. The diminution of barometric pressure which takes place all
over Asia during the summer months, and the increase in the winter,
are hence, no doubt, the results of the alternate heating and cooling
of the air over the continent.

The necessary and immediate results of such periodical changes of
pressure are winds, which, speaking generally, blow from the area of
greatest to that of least pressure--subject, however, to certain
modifications of direction, arising from the absolute motion of the
whole body of the air due to the revolution of the earth on its axis
from west to east. The south-westerly winds which prevail north of the
equator during the hot half of the year, to which navigators have
given the name of the south-west monsoon (the latter word being a
corruption of the Indian name for season), arise from the great
diminution of atmospheric pressure over Asia, which begins to be
strongly marked with the great rise of temperature in April and May,
and the simultaneous relatively higher pressure over the equator and
the regions south of it. This diminution of pressure, which continues
as the heat increases till it reaches its maximum in July soon after
the solstice, is followed by the corresponding development of the
south-west monsoon; and as the barometric pressure is gradually
restored, and becomes equalized within the tropics soon after the
equinox in October, with the general fall of temperature north of the
equator, the south-west winds fall off, and are succeeded by a
north-east monsoon, which is developed during the winter months by the
relatively greater atmospheric pressure which then occurs over Asia,
as compared with the equatorial region.

Although the succession of the periodical winds follows the progress
of the seasons as just described, the changes in the wind's direction
everywhere take place under the operation of special local influences
which often disguise the more general law, and make it difficult to
trace. Thus the south-west monsoon begins in the Arabian Sea with west
and north-westerly winds, which draw round as the year advances to
south-west and fall back again in the autumn by north-west to north.
In the Bay of Bengal the strength of the south-west monsoon is rather
from the south and south-east, being succeeded by north-east winds
after October, which give place to northerly and north-westerly winds
as the year advances. Among the islands of the Malay Archipelago the
force of the monsoons is much interrupted, and the position of this
region on the equator otherwise modifies the directions of the
prevailing winds. The southerly summer winds of the Asiatic seas
between the equator and the tropic do not extend to the coasts of
Java, and the south-easterly trade winds are there developed in the
usual manner. The China Sea is fully exposed to both monsoons, the
normal directions of which nearly coincide with the centre of the
channel between the continent of Asia and the eastern islands.

The south-west monsoon does not generally extend, in its character of
a south-west wind, over the land. The current of air flowing in from
over the sea is gradually diverted towards the area of least pressure,
and at the same time is dissipated and loses much of its original
force. The winds which pass northward over India blow as
south-easterly and easterly winds over the north-eastern part of the
Gangetic plain, and as south winds up the Indus. They seem almost
entirely to have exhausted their northward velocity by the time they
have reached the northern extremity of the great Indian plain; they
are not felt on the table-lands of Afghanistan, and hardly penetrate
into the Indus basin or the ranges of the Himalaya, by which
mountains, and those which branch off from them into the Malay
peninsula, they are prevented from continuing their progress in the
direction originally imparted to them.

Among the more remarkable phenomena of the hotter seas of Asia must be
noticed the revolving storms or cyclones, which are of frequent
occurrence in the hot months in the Indian Ocean and China Sea, in
which last they are known under the name of typhoon. The cyclones of
the Bay of Bengal appear to originate over the Andaman and Nicobar
islands, and are commonly propagated in a north-westward direction,
striking the east coast of the Indian peninsula at various points, and
then often advancing with an easterly tendency over the land, and
passing with extreme violence across the delta of the Ganges. They
occur in all the hot months, from June to October, and more rarely in
November, and appear to be originated by adverse currents from the
north meeting those of the south-west monsoon. The cyclones of the
China Sea also occur in the hot months of the year, but they advance
from north-east to south-west, though occasionally from east to west;
they originate near the island of Formosa, and extend to about the
10th degree of N. lat. They are thus developed in nearly the same
latitudes and in the same months as those of the Indian Sea, though
their progress is in a different direction. In both cases, however,
the storms appear to advance towards the area of greatest heat. In
these storms the wind invariably circulates from north by west through
south to east.

Rainfall.

The heated body of air carried from the Indian Ocean over southern
Asia by the south-west monsoon comes up highly charged with watery
vapour, and hence in a condition to release a large body of water as
rain upon the land, whenever it is brought into circumstances which
reduce its temperature in a notable degree. Such a reduction of
temperature is brought about along the greater part of the coasts of
India and of the Burmo-Siamese peninsula by the interruption of the
wind current by continuous ranges of mountains, which force the mass
of air to rise over them, whereby the air being rarefied, its specific
capacity for heat is increased and its temperature falls, with a
corresponding condensation of the vapour originally held in
suspension.

This explanation of the principal efficient cause of the summer rains
of south Asia is immediately based on an analysis of the complicated
phenomena actually observed, and it serves to account for many
apparent anomalies. The heaviest falls of rain occur along lines of
mountain of some extent directly facing the vapour-bearing winds, as
on the Western Ghats of India and the west coast of the Malay
peninsula. The same results are found along the mountains at a
distance from the sea, the heaviest rainfall known to occur anywhere
in the world (not less than 600 in. in the year) being recorded on the
Khasi range about 100 m. north-east of Calcutta, which presents an
abrupt front to the progress of the moist winds flowing up from the
Bay of Bengal. The cessation of the rains on the southern border of
Baluchistan, west of Karachi, obviously arises from the projection of
the south-east coast of Arabia, which limits the breadth of the
south-west monsoon air current and the length of the coast-line
directly exposed to it. The very small and irregular rainfall in Sind
and along the Indus is to be accounted for by the want of any obstacle
in the path of the vapour-bearing winds, which, therefore, carry the
uncondensed rain up to the Punjab, where it falls on the outer ranges
of the western Himalaya and of Afghanistan.

The diurnal mountain winds are very strongly marked on the Himalaya,
where they probably are the most active agents in determining the
precipitation of rain along the chain--the monsoon currents, as before
stated, not penetrating among the mountains. The formation of dense
banks of cloud in the afternoon, when the up wind is strongest, along
the southern face of the snowy ranges of the Himalaya, is a regular
daily phenomenon during the hotter months of the year, and heavy rain,
accompanied by electrical discharges, is the frequent result of such
condensation.

Too little is known of the greater part of Asia to admit of any more
being said with reference to this part of the subject, than to
mention a few facts bearing on the rainfall. In northern Asia there
is a generally equal rainfall of 19 to 29 in. between the Volga and
the Lena in Manchuria and northern China, rather more considerable
increase in Korea, Siam and Japan. At Tiflis the yearly fall is 22
in.; on the Caspian about 7 or 8 in.; on the Sea of Aral 5 or 6 in. In
south-western Siberia it is 12 or 14 in., diminishing as we proceed
eastward to 6 or 7 in. at Barnaul, and to 5 or 6 in. at Urga in
northern Mongolia. In eastern Siberia it is about 15 to 20 in. In
China we find about 23 in. to be the fall at Peking; while at Canton,
which lies nearly on the northern tropic and the region of the
south-west monsoon is entered, the quantity is increased to 78 in. At
Batavia in Java the fall is about 78 in.; at Singapore it is nearly
100 in. The quantity increases considerably on that part of the coast
of the Malay peninsula which is not sheltered from the south-west by
Sumatra. On the Tenasserim and Burmese coast falls of more than 200
in. are registered, and the quantity is here nowhere less than 75 or
80 in., which is about the average of the eastern part of the delta of
the Ganges, Calcutta standing at about 64 in. On the hills that flank
Bengal on the east the fall is very great. On the Khasi hills, at an
elevation of about 4500 ft., the average of ten years is more than 550
in. As much as 150 in. has been measured in one month, and 610 in. in
one year. On the west coast of the Indian peninsula the fall at the
sea-level varies from about 75 to 100 in., and at certain elevations
on the mountains more than 250 in. is commonly registered, with
intermediate quantities at intervening localities. On the east coast
the fall is far less, nowhere rising to 50 in., and towards the
southern apex of the peninsula being reduced to 25 or 30 in. Ceylon
shows from 60 to 80 in. As we recede from the coast the fall
diminishes, till it is reduced to about 25 or 30 in. at the head of
the Gangetic plain. The tract along the Indus to within 60 or 80 m. of
the Himalaya is almost rainless, 6 or 8 in. being the fall in the
southern portion of the Punjab. On the outer ranges of the Himalaya
the yearly fall amounts to about 200 in. on the east in Sikkim, and
gradually diminishes on the west, where north of the Punjab it is
about 70 or 80 in. In the interior of the chain the rain is far less,
and the quantity of precipitation is so small in Tibet that it can be
hardly measured. It is to the greatly reduced fall of snow on the
northern faces of the highest ranges of the Himalaya that is to be
attributed the higher level of the snow-line, a phenomenon which was
long a cause of discussion.

In Afghanistan, Persia, Asia Minor and Syria, winter and spring appear
to be the chief seasons of condensation. In other parts of Asia the
principal part of the rain falls between May and September, that is,
in the hottest half of the year. In the islands under the equator the
heaviest fall is between October and February. (R. S.)

FLORA AND FAUNA

The general assemblage of animals and plants found over northern Asia
resembles greatly that found in the parts of Europe which are adjacent
and have a similar climate. Siberia, north of the 50th parallel, has a
climate not much differing from a similarly situated portion of
Europe, though the winters are more severe and the summers hotter. The
rainfall, though moderate, is still sufficient to maintain the supply
of water in the great rivers that traverse the country to the Arctic
Sea, and to support an abundant vegetation. A similar affinity exists
between the life of the southern parts of Europe and that in the zone
of Asia extending from the Mediterranean across to the Himalaya and
northern China. This belt, which embraces Asia Minor, northern Persia,
Afghanistan, and the southern slopes of the Himalaya, from its
elevation has a temperate climate, and throughout it the rainfall is
sufficient to maintain a vigorous vegetation, while the summers,
though hot. and the winters, though severe, are not extreme. The
plants and animals along it are found to have a marked similarity of
character to those of south Europe, with which region the zone is
virtually continuous.

The extremely dry and hot tracts which constitute an almost unbroken
desert from Arabia, through south Persia and Baluchistan, to Sind, are
characterized by considerable uniformity in the types of life, which
closely approach to those of the neighbouring hot and dry regions of
Africa. The region of the heavy periodical summer rains and high
temperature, which comprises India, the Indo-Chinese peninsula, and
southern China, as well as the western part of the Malay Archipelago,
is also marked by much similarity in the plants and animals throughout
its extent. The area between the southern border of Siberia and the
margin of the temperate alpine zone of the Himalaya and north China,
comprising what are commonly called central Asia, Turkestan, Mongolia
and western Manchuria, is an almost rainless region, having winters of
extreme severity and summers of intense heat. Its animals and plants
have a special character suited to the peculiar climatal conditions,
more closely allied to those of the adjacent northern Siberian tract
than of the other bordering regions. The south-eastern parts of the
Malay Archipelago have much in common with the Australian continent,
to which they adjoin, though their affinities are chiefly Indian.
North China and Japan also have many forms of life in common. Much
still remains to be done in the exploration of China and eastern Asia;
but it is known that many of the special forms of this region extend
to the Himalaya, while others clearly indicate a connexion with North
America.

The foregoing brief review of the principal territorial divisions
according to which the forms of life are distributed in Asia,
indicates how close is the dependence of this distribution on climatic
conditions, and this will be made more apparent by a somewhat fuller
account of the main features of the flora and fauna.

Northern Asia.

_Flora._--The flora of the whole of northern Asia is in essentials the
same as that of northern Europe, the differences being due rather to
variations of species than of genera. The absence of the oak and of
all heaths east of the Ural may be noticed. Pines, larch, birch are
the principal trees on the mountains; willow, alders and poplars on
the lower ground. The northern limit of the pine in Siberia is about
70 deg. N.

Along the warm temperate zone, from the Mediterranean to the Himalaya,
extends a flora essentially European in character. Many European
species reach the central Himalaya, though few are known in its
eastern parts. The genera common to the Himalaya and Europe are much
more abundant, and extend throughout the chain, and to all elevations.
There is also a corresponding diffusion of Japanese and Chinese forms
along this zone, these being most numerous in the eastern Himalaya,
and less frequent in the west.

The truly tropical flora of the hotter and wetter regions of eastern
India is continuous with that of the Malayan peninsula and islands,
and extends along the lower ranges of the Himalaya, gradually becoming
less marked and rising to lower elevations as we go westward, where
the rainfall diminishes and the winter cold increases.

The vegetation of the higher and therefore cooler and less rainy
ranges of the Himalaya has greater uniformity of character along the
whole chain, and a closer general approach to European forms is
maintained; an increased number of species is actually identical,
among these being found, at the greatest elevations, many alpine
plants believed to be identical with species of the north Arctic
regions. On reaching the Tibetan plateau, with the increased dryness
the flora assumes many features of the Siberian type. Many true
Siberian species are found, and more Siberian genera. Some of the
Siberian forms, thus brought into proximity with the Indian flora,
extend to the rainy parts of the mountains, and even to the plains of
upper India. Assemblages of marine plants form another remarkable
feature of Tibet, these being frequently met with growing at
elevations of 14,000 to 15,000 ft. above the sea, more especially in
the vicinity of the many salt lakes of those regions.

The vegetation of the hot and dry region of the south-west of the
continent consists largely of plants which are diffused over Africa,
Baluchistan and Sind; many of these extend into the hotter parts of
India, and not a few common Egyptian plants are to be met with in the
Indian peninsula.

Indian region.

The whole number of species of plants indigenous in the region of
south-eastern Asia, which includes India and the Malayan peninsula and
islands, from about the 65th to the 105th meridian, was estimated by
Sir J.D. Hooker at 12,000 to 15,000. The principal orders, arranged
according to their numerical importance, are as follows:--Leguminosae,
Rubiaceae, Orchidaceae, Compositae, Gramineae, Euphorbiaceae,
Acanthaceae, Cyperaceae and Labiatae. But within this region there is
a very great variation between the vegetation of the more humid and
the more arid regions, while the characteristics of the flora on the
higher mountain ranges differ wholly from those of the plains. In
short, we have a somewhat heterogeneous assemblage of tropical,
temperate and alpine plants, as has been already briefly indicated, of
which, however, the tropical are so far dominant as to give their
character to the flora viewed as a whole. The Indian flora contains a
more general and complete illustration of almost all the chief natural
families of all parts of the world than any other country. Compositae
are comparatively rare; so also Gramineae and Cyperaceae are in some
places deficient, and Labiatae, Leguminosae and ferns in others.
Euphorbiaceae and Scrophulariaceae and Orchidaceae are universally
present, the last in specially large proportions.

The perennially humid regions of the Malayan peninsula and western
portion of the archipelago are everywhere covered with dense forest,
rendered difficult to traverse by the thorny cane, a palm of the genus
_Calamus_, which has its greatest development in this part of Asia.
The chief trees belong to the orders of Terebinthaceae, Sapindaceae,
Meliaceae, Clusiaceae, Dipterocarpaceae, Ternstroemiaceae,
Leguminosae, laurels, oaks and figs, with Dilleniaceae, Sapotaceae and
nutmegs. Bamboos and palms, with _Pandanus_ and _Dracaena_, are also
abundant. A similar forest flora extends along the mountains of
eastern India to the Himalaya, where it ascends to elevations varying
from 6000 to 7000 ft. on the east to 3000 or 4000 ft. on the west.

The arboreous forms which least require the humid and equable heat of
the more truly tropical and equatorial climates, and are best able to
resist the high temperatures and excessive drought of the northern
Indian hot months from April to June, are certain Leguminosae,.
_Bauhinia, Acacia, Butea_ and _Dalbergia, Bombax, Skorea, Nauclea,
Lagerstroemia_, and _Bignonia_, a few bamboos and palms, with others
which extend far beyond the tropic, and give a tropical aspect to the
forest to the extreme northern border of the Indian plain.

Of the herbaceous vegetation of the more rainy regions may be noted
the Orchidaceae, Orontiaceae, Scitamineae, with ferns and other
Cryptogams, besides Gramineae and Cyperaceae. Among these some forms,
as among the trees, extend much beyond the tropic and ascend into the
temperate zones on the mountains, of which may be mentioned _Begonia,
Osbeckia_, various Cyrtandraceae, Scitamineae, and a few epiphytical
orchids.

Of the orders most largely developed in south India, and more
sparingly elsewhere, may be named Aurantiaceae, Dipterocarpaceae,
Balsaminaceae, Ebenaceae, Jasmineae, and Cyrtandraceae; but of these
few contain as many as 100 peculiar Indian species. _Nepenthes_ may be
mentioned as a genus specially developed in the Malayan area, and
extending from New Caledonia to Madagascar; it is found as far north
as the Khasi hills, and in Ceylon, but does not appear on the Himalaya
or in the peninsula of India. The Balsaminaceae may be named as being
rare in the eastern region and very abundant in the peninsula. A
distinct connexion between the flora of the peninsula and Ceylon and
that of eastern tropical Africa is observable not only in the great
similarity of many of the more truly tropical forms, and the identity
of families and genera found in both regions, but in a more remarkable
manner in the likeness of the mountain flora of this part of Africa to
that of the peninsula, in which several species occur believed to be
identical with Abyssinian forms. This connexion is further established
by the absence from both areas of oaks, conifers and cycads, which, as
regards the first two families, is a remarkable feature of the flora
of the peninsula and Ceylon, as the mountains rise to elevations in
which both of them are abundant to the north and east. With these
facts it has to be noticed that many of the principal forms of the
eastern flora are absent or comparatively rare in the peninsula and
Ceylon.

The general physiognomy of the Indian flora is mainly determined by
the conditions of humidity of climate. The impenetrable shady forests
of the Malay peninsula and eastern Bengal, of the west coast of the
Indian peninsula, and of Ceylon, offer a strong contrast to the more
loosely-timbered districts of the drier regions of central India and
the north-western Himalaya. The forest areas of India include the
dense vegetation and luxuriant growth of the Tarai jungles at the foot
of the eastern Himalaya, and wide stretches of loosely-timbered
country which are a prevailing feature in the Central Provinces and
parts of Madras. Where the lowlands are highly cultivated they are
adorned with planted wood, and where they are cut off from rain they
are nearly completely desert.

The higher mountains rise abruptly from the plains; on their slopes,
clothed below almost exclusively with the more tropical forms, a
vegetation of a warm temperate character, chiefly evergreen, soon
begins to prevail, comprising Magnoliaceae, Ternstroemiaccae,
subtropical Rosaceae, rhododendron, oak, _Ilex, Symplocos_, Lauraceae,
_Pinus longifolia_, with mountain forms of truly tropical orders,
palms, _Pandanus, Musa, Vitis, Vernonia_, and many others. On the east
the vegetation of the Himalaya is most abundant and varied. The forest
extends, with great luxuriance, to an elevation of 12,000 ft., above
which the sub-alpine region may be said to begin, in which
rhododendron scrub often covers the ground up to 13,000 or 14,000 ft.
Only one pine is found below 8000 ft., above which several other
Coniferae occur. Plantains, tree-ferns, bamboos, several _Calami_, and
other palms, and _Pandanus_, are abundant at the lower levels. Between
4000 and 8000 ft. epiphytal orchids are very frequent, and reach even
to 10,000 ft. Vegetation ascends on the drier and less snowy mountain
slopes of Tibet to above 18,000 ft. On the west, with the drier
climate, the forest is less luxuriant and dense, and the hill-sides
and the valleys better cultivated. The warm mountain slopes are
covered with _Pinus longifolia_, or with oaks and rhododendron, and
the forest is not commonly dense below 8000 ft., excepting in some of
the more secluded valleys at a low elevation. From 8000 to 12,000 ft.,
a thick forest of deciduous trees is almost universal, above which a
sub-alpine region is reached, and vegetation as on the east continues
up to 18,000 ft. or more. The more tropical forms of the east, such as
the tree-ferns, do not reach west of Nepal. The cedar or deodar is
hardly indigenous east of the sources of the Ganges, and at about the
same point the forms of the west begin to be more abundant, increasing
in number as we advance towards Afghanistan.

The cultivated plants of the Indian region include wheat, barley, rice
and maize; various millets, _Sorghum, Penicillaria, Panicum_ and
_Eleusine_; many pulses, peas and beans; mustard and rape; ginger and
turmeric; pepper and capsicum; several Cucurbitaceae; tobacco,
_Sesamum_, poppy, _Crotolaria_ and _Cannabis_; cotton, indigo and
sugar; coffee and tea; oranges, lemons of many sorts; pomegranate,
mango, figs, peaches, vines and plantains. The more common palms are
_Cocos, Phoenix_ and _Borassus_, supplying cocoa-nut and toddy. Indian
agriculture combines the harvests of the tropical and temperate zones.
North of the tropic the winter cold is sufficient to admit of the
cultivation of almost all the cereals and vegetables of Europe, wheat
being sown in November and reaped early in April. In this same region
the summer heat and rain provide a thoroughly tropical climate, in
which rice and other tropical cereals are freely raised, being as a
rule sown early in July and reaped in September or October. In
southern India, and the other parts of Asia and of the islands having
a similar climate, the difference of the winter and summer half-years
is not sufficient to admit of the proper cultivation of wheat or
barley. The other cereals may be seen occasionally, where artificial
irrigation is practised, in all stages of progress at all seasons of
the year, though the operations of agriculture are, as a general rule,
limited to the rainy months, when alone is the requisite supply of
water commonly forthcoming.

The trees of India producing economically useful timber are
comparatively few, owing to the want of durability of the wood, in the
extremely hot and moist climate. The teak, _Tectona grandis_, supplies
the finest timber. It is found in greatest perfection in the forests
of the west coasts of Burma and the Indian peninsula, where the
rainfall is heaviest, growing to a height of 100 or 150 ft., mixed
with other trees and bamboos. The sal, _Shorea robusta_, a very
durable wood, is most abundant along the skirts of the Himalaya from
Assam to the Punjab, and is found in central India, to which the teak
also extends. The sal grows to a large size, and is more gregarious
than the teak. Of other useful woods found in the plains may be named
the babool, _Acacia_; toon, _Cedrela_; and sissoo, _Dalbergia_. The
only timber in ordinary use obtained from the Himalaya proper is the
deodar, _Cedrus deodara_. Besides these are the sandalwood,
_Santalum_, of southern India, and many sorts of bamboo found in all
parts of the country. The cinchona has recently been introduced with
complete success; and the mahogany of America reaches a large size,
and gives promise of being grown for use as timber.

Western Asia.

The flora of the rainless region of south-western Asia is continuous
with the desert flora of northern and eastern Africa, and extends from
the coast of Senegal to the meridian of 75 deg. E., or from the great
African desert to the border of the rainless tract along the Indus and
the southern parts of the Punjab. It includes the peninsula of Arabia,
the shores of the Persian Gulf, south Persia, and Afghanistan and
Baluchistan. On the west its limit is in the Cape Verde Islands, and
it is partially represented in Abyssinia.

The more common plants in the most characteristic part of this region
in southern Arabia are Capparidaceae, Euphorbiaceae, and a few
Leguminosae, a _Reseda_ and _Dipterygium_; palms, Polygonaceae, ferns,
and other cryptogams, are rare. The number of families relative to the
area is very small, and the number of genera and species equally
restricted, in very many cases a single species being the only
representative of an order. The aspect of the vegetation is very
peculiar, and is commonly determined by the predominance of some four
or five species, the rest being either local or sparingly scattered
over the area. The absence of the ordinary bright green colours of
vegetation is another peculiarity of this flora, almost all the plants
having glaucous or whitened stems. Foliage is reduced to a minimum,
the moisture of the plant being stored up in massive or fleshy stems
against the long-continued drought. Aridity has favoured the
production of spines as a defence from external attack, sharp thorns
are frequent, and asperities of various sorts predominate. Many
species produce gums and resins, their stems being encrusted with the
exudations, and pungency and aromatic odour is an almost universal
quality of the plants of desert regions.

The cultivated plants of Arabia are much the same as those of northern
India--wheat, barley, and the common _Sorghum_, with dates and lemons,
cotton and indigo. To these must be added coffee, which is restricted
to the slopes of the western hills. Among the more mountainous regions
of the south-western part of Arabia, known as Arabia Felix, the
summits of which rise to 6000 or 7000 ft., the rainfall is sufficient
to develop a more luxuriant vegetation, and the valleys have a flora
like that of similarly situated parts of southern Persia, and the less
elevated parts of Afghanistan and Baluchistan, partaking of the
characters of that of the hotter Mediterranean region. In these
countries aromatic shrubs are abundant. Trees are rare, and almost
restricted to _Pistacia, Celtis_ and _Dodonaea_, with poplars, and the
date palm. Prickly forms of _Statice_ and _Astragalus_ cover the dry
hills. In the spring there is an abundant herbaceous vegetation,
including many bulbous plants, with genera, if not species, identical
with those of the Syrian region, some of which extend to the Himalaya.

The flora of the northern part of Afghanistan approximates to that of
the contiguous western Himalaya. _Quercus Ilex_, the evergreen oak of
southern Europe, is found in forests as far east as the Sutlej,
accompanied with other European forms. In the higher parts of
Afghanistan and Persia Boraginaceae and thistles abound; gigantic
Umbelliferae, such as _Ferula, Galbanum, Dorema, Bubon, Peucedanum,
Prangos_, and others, also characterize the same districts, and some
of them extend into Tibet.

The flora of Asia Minor and northern Persia differs but little from
that of the southern parts of Europe. The mountains are clothed, where
the fall of rain is abundant, with forests of _Quercus, Fagus, Ulmus,
Acer, Carpinus_ and _Corylus_, and various Coniferae. Of these the
only genus that is not found on the Himalaya is _Fagus_. Fruit trees
of the plum tribe abound. The cultivated plants are those of southern
Europe.

Eastern Asia.

The vegetation of the Malayan Islands is for the most part that of the
wetter and hotter region of India; but the greater uniformity of the
temperature and humidity leads to the predominance of certain tropical
forms not so conspicuous in India, while the proximity of the
Australian continent has permitted the partial diffusion of Australian
types which are not seen in India. The liquidambar and nutmeg may be
noticed among the former, the first is one of the most conspicuous
trees in java, on the mountains of the eastern part of which the
casuarina, one of the characteristic forms of Australia, is also
abundant. Rhododendrons occur in Borneo and Sumatra, descending to the
level of the sea. On the mountains of Java there appears to be no
truly alpine flora, _Saxifraga_ is not found. In Borneo some of the
temperate forms of Australia appear on the higher mountains. On the
other islands similar characteristics are to be observed, Australian
genera extending to the Philippines, and even to southern China.

The analysis of the Hong Kong flora indicates that about three-fifths
of the species are common to the Indian region, and nearly all the
remainder are either Chinese or local forms. The number of species
common to southern China, Japan and northern Asia is small. The
cultivated plants of China are, with a few exceptions, the same as
those of India South China, therefore seems, botanically hardly
distinct from the great Indian region, into which many Chinese forms
penetrate, as before noticed. The flora of north China, which is akin
to that of Japan, shows manifest relation to that of the neighbouring
American continent, from which many temperate forms extend, reaching
to the Himalaya, almost as far as Kashmir. Very little is known of the
plants of the interior of northern China, but it seems probable that a
complete botanical connexion is established between it and the
temperate region of the Himalaya.

Central Asia.

The vegetation of the dry region of central Asia is remarkable for the
great relative number of Chenopodiaceae, _Salicornia_ and other salt
plants being common; Polygonaceae also are abundant, leafless forms
being of frequent occurrence, which gives the vegetation a very
remarkable aspect. Peculiar forms of Leguminosae also prevail, and
these with many of the other plants of the southern and drier regions
of Siberia, or of the colder regions of the desert tracts of Persia
and Afghanistan, extend into Tibet, where the extreme drought and the
hot (nearly vertical) sun combine to produce a summer climate not
greatly differing from that of the plains of central Asia.

Zoological Regions.

_Fauna._--The zoological provinces of Asia correspond very closely
with the botanical. The northern portion of Asia, as far south as the
Himalaya, is not zoologically distinct from Europe, and these two
areas, with the strip of Africa north of the Atlas, constitute the
Palaearctic region of Dr. Sclater, whose zoological primary divisions
of the earth have met with the general approval of naturalists. The
south-eastern portion of Asia with the adjacent islands of Sumatra,
Java, Borneo and the Philippines, form his Indian region. The extreme
south-west part of the continent constitutes a separate zoological
district, comprising Arabia, Palestine and southern Persia, and
reaching, like the hot desert botanical tract, to Baluchistan and
Sind, it belongs to what Dr. Sclater calls the Ethiopian region, which
extends over Africa, south of the Atlas. Celebes, Papua, and the other
islands east of Java beyond Wallace's line fall within the Australian
region.

Mammals and birds.

Nearly all the mammals of Europe also occur in northern Asia, where
however, the Palaearctic fauna is enriched by numerous additional
species. The characteristic groups belong mostly to forms which are
restricted to cold and temperate regions. Consequently the Quadrumana,
or monkeys, are nearly unrepresented, a single species occurring in
Japan, and one or two others in northern China and Tibet.
Insectivorous bats are numerous, but the frugivorous division of this
order is only represented by a single species in Japan. Carnivora are
also numerous, particularly the frequenters of cold climates, such as
bears, weasels, wolves and foxes. Of the Insectivora, numerous forms
of moles, shrews and hedgehogs prevail. The Rodents are also well
represented by various squirrels, mice, and hares. Characteristic
forms ot this order in northern Asia are the marmots (_Arctomys_) and
the pikas or tailless hares (_Lagomys_). The great order of Ungulata
is represented by various forms of sheep, as many as ten or twelve
wild species of _Ovis_ being met with in the mountain chains of Asia,
and more sparingly by several peculiar forms of antelope, such as the
saiga (_Saiga tatarica_) and the _Gazella gutturosa_, or yellow sheep.
Coming to the deer, we also meet with characteristic forms in northern
Asia, especially those belonging to the typical genus _Cervus_. The
musk deer (_Moschus_) is also quite restricted to northern Asia, and
is one of its most peculiar types.

The ornithology ot northern Asia is even more closely allied to that
of Europe than the mammal fauna. Nearly three fourths of the
well-known species of Europe extend through Siberia into the islands
of the Japanese empire. Here again, we have an absence of all tropical
forms, and a great development of groups characteristic of cold and
temperate regions. One of the most peculiar of these is the genus
_Phasianus_, of which splendid birds all the species are restricted in
their wild state to northern Asia. The still more magnificently clad
gold pheasants (_Thaumalea_), and the eared pheasants (_Crossoptilon_)
are also confined to certain districts in the mountains of north
eastern Asia. Amongst the _Passeres_, such forms as the larks, stone
chats, finches, linnets, and grosbeaks are well developed and exhibit
many species.

The mammal fauna of the Indian region of Asia is much more highly
developed than that of the Palaearctic. The Quadrumana are represented
by several peculiar genera, amongst which are _Semnopithecus_,
_Hylobates_ and _Simia_. Two peculiar forms of the Lemurine group are
also met with. Both the insectivorous and frugivorous divisions of the
bats are well represented. Amongst the Insectivora very peculiar forms
are found, such as _Gymnura_ and _Tupaia_. The _Carnivora_ are
likewise numerous, and this region may be considered as the true home
of the tiger, though this animal has wandered far north into the
Palaearctic division of Asia. Other characteristic Carnivora are
civets, various ichneumons, and the benturong (_Arctictis_). Two
species of bears are likewise restricted to the Indian region. In the
order of Rodents squirrels are very numerous and porcupines of two
genera are met with. The Indian region is the home of the Indian
elephant--one of the two sole remaining representatives of the order
Proboscidea. Of the Ungulates, four species of rhinoceros and one of
tapir are met with, besides several peculiar forms of the swine
family. The Bovidae or hollow-horned ruminants, are represented by
several genera of antelopes, and by species of true _Bos_--such as _B.
sondaicus_, _B. frontalis_ and _B. bubalus_. Deer are likewise
numerous, and the peculiar group of chevrotains (_Tragulus_) is
characteristic of the Indian region. Finally, this region affords us
representatives of the order Edentata, in the shape of several species
of _Manis_, or scaly ant-eater.

The assemblage of birds of the Indian region is one of the richest and
most varied in the world, being surpassed only by that of tropical
America. Nearly every order, except that of the Struthiones or
ostriches, is well represented, and there are many peculiar genera not
found elsewhere, such as _Buceros_, _Harpactes_, _Lophophorus_,
_Euplocamus_, _Pajo_ and _Ceriornis_. The _Phasianidae_ (exclusive of
true _Phasianus_) are highly characteristic ot this region, as are
likewise certain genera of barbets (_Megalaema_), parrots
(_Palaeornis_), and crows (_Dendrocitta_, _Urocissa_ and _Cissa_). The
family _Eurylaemidae_ is entirely confined to this part of Asia.

The Ethiopian fauna plays but a subordinate part in Asia, intruding
only into the south-western corner, and occupying the desert districts
of Arabia and Syria, although some of the characteristic species reach
still farther into Persia and Sind, and even into western India. The
lion and the hunting leopard, which may be considered as in this epoch
at least, Ethiopian types extend thus far, besides various species of
jerboa and other desert-loving forms.

In the birds, the Ethiopian type is shown by the prevalence of larks
and stone chats, and by the complete absence of the many peculiar
genera of the Indian region.

The occurrence of mammals of the Marsupial order in the Molucca
Islands and Celebes, while none have been found in the adjacent
islands of Java and Borneo, lying on the west of Wallace's line, or in
the Indian region, shows that the margin of the Australian region has
here been reached. The same conclusion is indicated by the absence
from the Moluccas and Celebes of various other Mammals, Quadrumana,
Carnivora, Insectivora and Ruminants, which abound in the western part
of the Archipelago. Deer do not extend into New Guinea, in which
island the genus _Sus_ appears to have its eastern limit. A peculiar
form of baboon, _Cynopithecus_, and the singular ruminant, _Anoa_,
found in Celebes, seem to have no relation to Asiatic animals, and
rather to be allied to those in Africa.

The birds of these islands present similar peculiarities. Those of the
Indian region abruptly disappear at, and many Australian forms reach
but do not pass, the line above spoken of. Species of birds akin to
those of Africa also occur in Celebes.

Of the marine orders of Sirenia and Cetacea the Dugong, _Halicore_, is
exclusively found in the Indian Ocean and a dolphin, _Platanista_,
peculiar to the Ganges, ascends that river to a great distance from
the sea.

Fishes.

Of the sea fishes of Asia, among the Acanthopterygii, or spiny-rayed
fishes, the _Percidae_, or perches, are largely represented, the genus
_Serranus_, which has only one species in Europe, is very numerous in
Asia, and the forms are very large. Other allied genera are abundant
and extend from the Indian seas to eastern Africa. The Squamipennes,
or scaly-finned fishes, are principally found in the seas of southern
Asia, and especially near coral reefs. The _Mullidae_ or red mullets
are largely represented by genera differing from those of Europe. The
_Polynemidae_, which range from the Atlantic through the Indian Ocean
to the Pacific, supply animals from which isinglass is prepared; one
of them, the mango fish, esteemed a great delicacy, inhabits the seas
from the Bay of Bengal to Siam. The _Sciaenidae_ extend from the Bay
of Bengal to China, but are not known to the westward. The
_Stromateidae_, or pomfrets, resemble the dory, a Mediterranean form,
and extend to China and the Pacific. The sword fishes _Xiphidae_, the
lancet fishes, _Acanthuridae_, and the scabbard fishes, _Trichuridae_,
are distributed through the seas of south Asia. Mackerels of various
genera abound, as well as gobies, blenniesm and mullets.

Among the Anacanthim, the cod family so well known in Europe shows but
one or two species in the seas of south Asia, though the soles and
allied fishes are numerous along the coasts. Of the Physostomi, the
siluroids are abundant in the estuaries and muddy waters; the habits
of some of these fishes are remarkable, such as that of the males
carrying the ova in their mouths till the young are hatched. The small
family of _Scopelidae_ affords the gelatinous _Harpodon_, or bumalo.
The gar-fish and flying fishes are numerous, extending into the seas
of Europe. The _Clupeidae_ or herrings, are most abundant, and
anchovies, or sardines, are found in shoals, but at irregular and
uncertain intervals. The marine eels, _Muraenidae_, are more numerous
towards the Malay Archipelago than in the Indian seas. Forms of
sea-horses (_Hippocampus_), pipe-fishes (_Syngnathus_), fife-fishes
(_Sclerodermus_), and sun-fish, globe-fish, and other allied forms of
_Gymnodontes_, are not uncommon.

Of the cartilaginous fishes, Chondropterygii, the true sharks and
hammer-headed sharks, are numerous. The dog-fish also is found, one
species extending from the Indian seas to the Cape of Good Hope. The
saw-fishes, _Pristidae_, the electrical rays, _Torpedinae_, and
ordinary rays and skates, are also found in considerable numbers.

The fresh waters of southern Asia are deficient in the typical forms
of the Acanthopterygii, and are chiefly inhabited by carp, siluroids,
simple or spined eels, and the walking and climbing fishes. The
_Siluridae_ attain their chief development in tropical regions. Only
one _Silurus_ is found in Europe, and the same species extends to
southern Asia and Africa. The _Salmonidae_ are entirely absent from
the waters of southern Asia, though they exist in the rivers that flow
into the Arctic Ocean and the neighbouring parts of the northern
Pacific, extending perhaps to Formosa; and trout, though unknown in
Indian rivers, are found beyond the watershed of the Indus, in the
streams flowing into the Caspian. The _Cyprinidae_, or carp, are
largely represented in southern Asia, and there grow to a size unknown
in Europe; a _Barbus_ in the Tigris has been taken of the weight of
300 lb. The chief development of this family, both as to size and
number of forms, is in the mountain regions with a temperate climate;
the smaller species are found in the hotter regions and in the
low-lying rivers. Of the _Clupeidae_, or herrings, numerous forms
occur in Asiatic waters, ascending the rivers many hundred miles; one
of the best-known of Indian fishes, the hilsa, is of this family. The
sturgeons, which abound in the Black Sea and Caspian, and ascend the
rivers that fall into them, are also found in Asiatic Russia, and an
allied form extends to southern China. The walking or climbing fishes,
which are peculiar to south-eastern Asia and Africa, are organized so
as to be able to breathe when out of the water, and they are thus
fitted to exist under conditions which would be fatal to other fishes,
being suited to live in the regions of periodical drought and rain in
which they are found.

Insects.

The insects of all southern Asia, including India south of the
Himalaya, China, Siam and the Malayan Islands, belong to one group;
not only the genera, but even the species are often the same on the
opposite sides of the Bay of Bengal. The connexion with Africa is
marked by the occurrence of many genera common to Africa and India,
and confined to those two regions, and similarities of form are not
uncommon there in cases in which the genera are not peculiar. Of
Coleopterous insects known to inhabit east Siberia, nearly one-third
are found in western Europe. The European forms seem to extend to
about 30 deg. N., south of which the Indo-Malayan types are met with,
Japan being of the Europeo-Asiatic group. The northern forms extend
generally along the south coast of the Mediterranean up to the border
of the great desert, and from the Levant to the Caspian.

Domesticated animals.

Of the domesticated animals of Asia may first be mentioned the
elephant. It does not breed in captivity, and is not found wild west
of the Jumna river in northern India. The horse is produced, in the
highest perfection in Arabia and the hot and dry countries of western
Asia. Ponies are most esteemed from the wetter regions of the east,
and the hilly tracts. Asses are abundant in most places, and two wild
species occur. The horned cattle include the humped oxen and buffaloes
of India, and the yak of Tibet. A hybrid between the yak and Indian
cattle, called zo, is commonly reared in Tibet and the Himalaya. Sheep
abound in the more temperate regions, and goats are universally met
with; both of these animals are used as beasts of burden in the
mountains of Tibet. The reindeer of northern Siberia call also for
special notice; they are used for the saddle as well as for draught.
(R. S.)

ETHNOLOGY

Racial types.