Everywhere amongst these border tribes are met groups of aborigines, who present more or less regular features which are described by various travellers as "Caucasic" or "European." Thus the _Kiu-tse_, who are the _Khanungs_ of the English maps, and are akin to the large _Lu-tse_ family (_Melam_, _Anu_, _Diasu_, etc.), reminded Prince Henri of some Europeans of his acquaintance[454], and he speaks of the light colour, straight nose and eyes, and generally fine type of the Yayo (Yao), as the Chinese call them, but whose real name is _Lin-tin-yu_. The same Caucasic element reappears in a pronounced form amongst the indigenous populations of Tonking, to whom A. Billet has devoted an instructive monograph[455]. This observer, who declares that these aborigines are quite distinct both from the Chinese and the Annamese, groups them in three main divisions--_Tho_, _Nong_, and _Man_[456]--all collectively called _Moi_, _Muong_, and _Myong_ by the Annamese. The Thos, who are the most numerous, are agriculturists, holding all the upland valleys and thinning off towards the wooded heights. They are tall compared to the Mongols (5 ft. 6 or 7 in.), lighter than the Annamese, round-headed, with oval face, deep-set straight eyes, low cheek-bones, straight and even slightly aquiline nose not depressed at root, and muscular frames. They are a patient, industrious, and frugal people, now mainly subject to Chinese and Annamese influences in their social usages and religion. Very peculiar nevertheless are some of their surviving customs, such as the feast of youth, the pastime of swinging, and especially chess played with living pieces, whose movements are directed by two players. The language appears to be a Shan dialect, and to this family the writer affiliates both the Thos and the Nongs. The latter are a much more mixed people, now largely assimilated to the Chinese, although the primitive type still persists, especially amongst the women, as is so often the case. A. Billet tells us that he often met Nong women "with light and sometimes even red hair[457]." It is extremely interesting to learn that the Mans came traditionally "from a far-off western land where their forefathers were said to have lived in contact with peoples of white blood thousands of years ago." This tradition, which would identify them with the above-mentioned Man-tse, is supported by their physical appearance--long head, oval face, small cheek-bones, eyes without the Mongol fold, skin not yellowish but rather "browned by the sun," regular features--in nothing recalling the traits of the yellow races. Let us now turn to M. R. Verneau's comments on the rich materials brought together by A. Billet, in whom, "being not only a medical man, but also a graduate in the natural sciences, absolute confidence may be placed[458]."