Siam has a monsoon climate—the wet season, May to October, corresponding with the prevalence of the S.W. mon soon in the Bay of Bengal. The full force of the monsoon is broken by the western frontier hills so that the average rainfall of Bangkok is about 5o inches and of Chieng Mai about 42 in. The temperature during the wet season averages 65-75° F at night and 75-85° F by day; but breaks in the rains occur which are hot and steamy. The cool season begins with the commence ment of the N.E. monsoon in November. Siam then enjoys cool nights (40--50° F) and day temperatures rarely as high as 90° F in the shade; but the east coast of the Malay Peninsula receives the full force of the north easterly gales. In February the north erly current begins to lose strength and the gradual heating of the land produces local sea breezes along the coast. Inland, tempera ture rises to over oo° F, but the extreme continental heats of India are unknown. The comparative humidity of the atmosphere makes the climate trying for Europeans.
Flora.—In its flora and fauna Siam combines the forms of Burma and the Shan States with those of Malaya and Cambodia. The coast region is characterised by mangroves, Pandanus, rat tans and similar palms; the central region by rice fields, coco-nut and areca palms, and tropical economic plants; the temperate uplands of the interior are forested and contain some Himalayan and Japanese species—oaks, pines, chestnuts, peach and apple trees, raspberries, honeysuckle, vines, saxifrages, Cichoraceae, anemones and Violaceae; there are many valuable timber trees— teak sappan, eagle-wood, wood-oil (Hopea), and other Diptero carpaceae, Cedrelaceae, Pterocarpaceae, Xylia, ironwood and other dye-woods and resinous trees, these last forming in many districts a large proportion of the more open forests with an undergrowth of bamboo. The chief products of the plains are rice (the staple export), pepper, sirib, sago, sugar cane, coco-nut, betel, palmyra or sugar and attap palms ; banana, durian, pom melo, guava, bread fruit, mango, pineapple, custard apple, mangosteen and other fruits.
Fauna.—Among the big game animals are the elephant, tiger, leopard, fishing-cat, leopard-cat and other species of wild cat, honey-bear, large sloth-bear, and one- and two-horned rhinoceros. Wild cattle include the gaur, banting and water buffalo. The goat antelope, several varieties of deer, wild pig, rats, bats and monkeys also exist. There are 56 varieties of snakes, of which only 12 are poisonous. Crocodiles haunt the rivers and estuaries. Fresh and salt water fish are numerous and, after rice, form the main food of the population. The country is rich in birds many of
which are common to Burma and Cambodia.
The census of 1929 gave a population of 11, 506,207. There were 10,493,304 Siamese and Laos, 445,274 Chi nese, 379,618 Indians and Malays, and the rest a mixture of Cam bodians, Burmese Indian, Mon, Karen, Annamite, Kache, Lawa and others. There are about 1,80o Europeans and Americans mostly resident in Bangkok. The Siamese inhabit central Siam principally, but extend into the nearer districts of the other sec tions. Laos predominate in northern and eastern Siam; Malays mingle with Siamese in southern Siam ; Chinese are everywhere but mostly in the towns. Bangkok, the capital, with some 350,000 inhabitants, is about one-third Chinese ; in the suburbs are settlements of Mons, Burmese, Annamites and Cambodians, descendants of ancient prisoners of war. The Eurasian popula tion is very small compared with that of other large Eastern cities. Of the tribes in the mountains some are remnants of very ancient inhabitants, probably of the Mon-Khmer family, who were sup planted by a later influx of more civilised Khmers from the south east, the fore-runners and part ancestors of the Siamese, and were still farther thrust into the remoter hills when the Lao-Tai descended from the north. Of these the principal are the Lawa, Lamet, Ka Hok, Ka Yuen and Kamoo ; the last four collectively are known to the Siamese as Ka. Other immigrant tribes include the Karens (about 6o,000) of the western frontier range, off shoots from the main tribes on the Burma side of the range and possibly of Burma-Tibetan origin; the Lu, Yao, Yao Yin, Meo and Mussur, who have Yunnanese characteristics, and possibly entered northern Siam since the beginning of the 19th century; a small tribe called Chong, behind Chantabun ; and the Sakei and Semang in the higher ranges of southern Siam. The last three have Negrito characteristics and may represent a race far older even than the ancient Ka.
The typical Siamese is of medium height, well formed, with olive complexion, darker than the Chinese, fairer than the Malays; eyes well shaped but slightly inclined to the oblique ; broad flat nose ; prominent lips; face wide across the cheek bones; chin short. A thin moustache is common; any beard is plucked out. Hair is black, coarse and cut short. Lips usually deep red and teeth black as a result of chewing betel. The children are pretty but early lose their charm.