Page:Encyclopædia Britannica, Ninth Edition, v. 12.djvu/764

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740
HOR — HOR
740

740 INDIA [PHYSICAL GEOGRAPHY. south-west monsoon. The characteristics of a weak mon soon are great irregularity in the distribution of the rainfall over the whole of India, and the occurrence of heavy local rainfalls, which tend, by a law of rainfall and of air-motion, to recur over the same limited areas. The irregularity of rainfall distribution is often shown by the persistent and prolonged absence of rain over considerable areas. These areas of drought and famine are partly marked off by nature, depending to a certain extent on the geographical features and position of the district. Thus the rains are more likely to fall below the amount necessary for cultiva tion in the dry region of the Deccan or in Upper India, than over the Malabar coast area or the province of Bengal." FLORA. Flora. Unlike many other large geographical areas, India is remarkable for having no distinctive botanical features peculiar to itself. It differs conspicuously in this respect from such countries as Australia or South Africa. Its vegetation is in point of fact of a composite character, and is constituted by the meeting and more or less blending of adjoining floras, of those of Persia and the south-eastern Mediterranean area to the north-west, of Siberia to the north, of China to the east, and of Malaya to the south-east. Our space does not admit of any minute discussion of the local features peculiar to separate districts, but regarded broadly, four tolerably distinct types present themselves. Hima- Himalayan. The base of the Himalayas is occupied layas. by a narrow belt forming an extreme north-western extension of the Malayan type described below. Above that there is a rich temperate flora which in the eastern chain may be regarded as forming an extension of that of northern China, gradually assuming westwards more and more of a European facies. Magnolia, Aucuba, Abclia, and Skimmia may be mentioned as examples of Chinese genera found in the eastern Himalayas, and the tea-tree grows wild in Assam. The same coniferous trees are common to both parts of the range. Pinus longij olia extends to the Hindu-Kush ; P. excelsa is found universally except in Sikkim, and has its European analogue in P. Pence, found in the mountains of Greece. Abies smithiana extends into Afghanistan ; Abies webbiana forms dense forests at altitudes of 8000 to 12,000 feet, and ranges from Bhutan to Kashmir ; several junipers and the common yew (Taxus baccata) also occur. The deodar (Ccdrus Deodara), which is indigenous to the mountains of Afghanistan and the north-west Himalaya, is nearly allied to the Atlantic cedar and to the cedar of Lebanon, a form of which has recently been found in Cyprus. A notable further in stance of the connexion of the western Himalayan flora with that of Europe is the holm oak (Quercus Ilex), which is characteristic of the Mediterranean region. The upper levels of the Himalayas slope northwards gradually to the Tibetan uplands, over which the Siberian temperate vegetation ranges. This is part of the great temperate flora which, with locally individualized species, but often with identical genera, ranges over the whole of the temperate zone of the northern hemisphere. In the western Himalayas this upland flora is marked by a strong admixture of European species, such as the columbine (Aquilegia) and hawthorn (Cratccgus Oxyacantha}. These disappear rapidly eastward, and are scarcely found beyond Kumdun. North- North-Western. This is best marked in Sind and the west. Punjab, where the climate is very dry (the rainfall averag ing less than 15 inches), and where the soil, though fertile, is wholly dependent on irrigation for its cultivation. The flora is a poor one in number of species, and is essentially identical with that of Persia, southern Arabia, and Egypt. The low scattered jungle contains such characteristic species as Gapparis aphylla, Acacia arabica (babul), Pojmhis evph- ratica (the "willows" of Ps. cxxxvii. 2), Salvadora persica (erroneously identified by Iloyle with the mustard of Matt, xiii. 31), tamarisk, Zizi/phus, Lotus, &c. More than nine- tenths of the Sind vegetation is estimated to be indigenous to Africa. The dry flora extends somewhat in a south east direction, and then blends insensibly with that of the western peninsula ; some species representing it are found in the upper Gangetic plain, and a few are widely distri buted in dry parts of the country. Malayan. This Sir Joseph Hooker describes as form- ^ ing " the bulk of the flora of the perennially humid and regions of India, as of the whole Malayan peninsula, the Ma Upper Assam valley, the Khasi mountains, the forests of ^ e the base of the Himalaya from the Brahmaputra to Nepal, of the Malabar coast, and of Ceylon." It is not of course intended that over this wide and disjointed area there is an actual identity of species ; but the affinities and general agreement of facies are sufficiently close to leave no doubt that they belong essentially to one and the same flora. A few illustrations must suffice : pitcher-plants (Nepenthes), so richly developed in Borneo, occur at Singapore, on the Khasi mountains, and in Ceylon, while they are absent from the western peninsula ; wood-oil trees (Dipterocarpece), which abound in the forests of the Malayan archipelago, are well represented by species individualized by isolation in the Malayan peninsula, Ceylon, and southern India; the gamboge of Singapore is scarcely distinguishable botani- cally from the Ceylon species ; rubber-yielding trees are characteristic, such are the climbing Apocynacccc found in the Malayan peninsula and Borneo, and the well-known Ficus elastica, indigenous to Assam and Java ; numerous palms and several species of Cycas also distinguish this flora from that of the western peninsula. Teak (Tectona grandis), which is indigenous to the Malayan archipelago, is native to both peninsulas as far as 25 N. lat., and is more tolerant of a dry climate than most of its associates. Western Peninsula. This type is difficult to characterize, r e and is in many respects intermediate between the two just Ind preceding. It occupies a comparatively dry area, with a rainfall under 75 inches. In respect to positive affinities, Sir Joseph Hooker has pointed out some relations with the flora of tropical Africa as evidenced by the prevalence of such genera as Greivia and Impatiens, and the absence, common to both countries, of oaks and pines which abound in the Malayan archipelago. Tke annual vegetation which springs up in the rainy season includes numerous genera, such as Sida and Indigofera, which are largely represented both in Africa and Hindustan. Palms also in both countries are scanty, the most notable in southern India being the wild date (Phoenix syhestris) ; Borassus and the cocoa- nut are cultivated. The forests, though occasionally very dense, as in the western Ghats, are usually drier and more open than those of the Malayan type, and are often scrubby. The most important timber trees are the toon (Cedrela Toona), sal (Shorea robttsta), the present area of which forms two belts separated by the Gangetic plain, satin wood (Chloroxylon Sivietenia), common in the drier parts of the peninsula, sandalwood, especially charac teristic of Mysore, iron-wood (Mesua ferrea), and teak, which has already been alluded to. 1 1 For a general sketch of the flora of India recourse must still be had to the introductory essay to the Flora Indica, published by Hooker and Thomson in 1855. The Flora of British India, the preparation of which is (1881) in progress at Kew, will comprise brief descriptions of all the species known to science up to the date of publication. But although no complete analysis of the vegetation is yet possible, its general features are now tolerably well understood.

[For the above section on the Flora we are indebted to Mr W. T. T. Dyer of Kcw.]