Pallegoix mentions one or two varieties of fish that are interesting, and, so far as known, peculiar to Siamese waters. One, "a large fish, called the mengphu, weighing from thirty to forty pounds, of a bright greenish-blue color, will spring out of the water to attack and bite bathers." He says there "is also a tetraodon, called by the Siamese the moon, without teeth, but with jaws as sharp as scissors. It can inflate itself so as to become round as a ball. It attacks the toes, the calf, and the thighs of bathers, and, as it carries away a portion of the flesh, a wound is left which it is difficult to heal." Of centipedes, scorpions, ants, mosquitoes, and the various pests and plagues common to all tropical countries it is not necessary to speak in detail. Sir John Bowring considered that sugar was likely to become the principal export of Siam, but thus far it would seem that rice has taken the precedence. The gutta-percha tree, all kinds of palms, and of fruits a vast and wonderful variety (among which are some peculiar to Siam), are abundant. The durian and mangosteen are the most remarkable, and have already been described. So far as is known, they grow only in the regions adjacent to the Gulf of Siam and the Straits of Sunda. And though there are many fruits common to these and to all tropical countries which are more useful (such as the banana, of which there are said to be in Siam not less than fifty varieties, "in size from a little finger to an elephant's tusk"), there are none more curious than these. The season of the mangosteen is the same with that of the durian. The tree grows about fifteen feet high, and the foliage is extremely glossy and dark. The fruit may be eaten in large quantities with safety, and is of incomparable delicacy of flavor. No fruit in the world has won such praises as the mangosteen. Of the mineral treasures of Siam, enough has been already indicated in the description of the wealth and magnificence which is everywhere apparent. We need only add that coal of excellent quality and in great abundance has been recently discovered, and that the country is also rich in petroleum, which awaits the wells and refineries by which it may be profitably used. Gold and silver mines are both known but little is produced from them. The government is obliged to import Mexican dollars in order to melt and recoin them in the new mint. CHAPTER XVIII. CHRISTIAN MISSIONS IN SIAM--THE OUTLOOK FOR THE FUTURE