OSTIAKS, or OSTYAKS, a tribe of Finnish origin, who. inhabit the basin of the Obi in western Siberia ; a few them on the flat lands of the Obi, and the best investigators (Castren, Lerberg, A. Scluenck) consider the trans-Uralian Ostiaks and Samoyedes as identical with the Yugra of the Russian annals During the Russian conquest their Obdorsk, and elsewhere. The total number of the Ostiaks may be estimated at a little over 27,000. Those on the Irtish are mostly settled, and have adopted the manner of life of Russians and Tartars. Those on the Obi are mostly nomads; along with 8000 Sarnoyedes in the districts of Beryozoff and Surgut, they own 93,600 reindeer. The Obi Ostiaks are Russified to a great extent. They live almost exclusively by fishing, buying from Russian merchants corn for bread, the use of which has become widely diffused.

The Ostiaks call themselves Ass-yakh (people of the Obi), and it is supposed that their present dosignation is a corruption of this name. By language they belong (CastMn, Reiseberidde, Reisebriefe ; Ahlqvist, Ofvers. of Finska Vet.-Soc. Furl., xxi.) to the Ugrian blanch of the eastern Finnish stem,--a classification confirmed by a grammar of their language, compilod in 1875, in Hungarian, by Hunfalvy. All the Ostiaks speak the same language, mixed to some extent with foreign elements ; but three or four leading dialects can be distinguished.

The Ostiaks are middle-sized, or of low stature, mostly meagre, and not ill made, however clumsy their apl,carance in winter, in their thick fur-clothes. The extremities are fine, and the feet are usually small. The skull is brachyceplialic, mostly of moderate size and height. The hair is dark and soft for the most part, fair and reddish individuals being rare ; the eyes are dark, generally narrow ; the nose is flat and broad; the mouth is large and with thick lips ; the beard is scanty. The younger men and women are sometimes of an agreeable appearance. The Alongolian type is more strongly pronounced in the women than in the men. On the whole, the Ostiaks arc not a pure race ; the purest type is found among the fishers on the Obi, the reindeer-breeders of the tundra being largely intermixed with Samoyedes (see Castr6n ; Fr Finseh's Relic smack ltrest-Sibirie4, Sm.).

Investigators am unanimous in describing them as very kind, gentle, and honest ; rioting is almost quite unknown among them, as also theft, this last occurring only in the vicinity of Hessian settlements, and the only penalty enforced being the restitution twofold of the propel ty stolen. The farther they are removed from contact with Russian dealers and traders the higher do their moral qualities become (Middendorff and CastMn).

They are very skilful in the arts they practise, especially in carving wood and bone, tanning (with egg-yolk and brains), preparation of implements from birch bark, Re. Some of their carved or decorated bark implements (like those figured in Middendorf-l.'s Sibirische Reise, iv. 2) show great artistic skill. Only a few have guns, the great majority continuing to hunt with bow and mows.

Their folk-lore, like to that of other Finnish stems, is imbued with a sleep feeling of natural poetry, and reflects also the sadness, or even the despair, which has been noticed among them. The number of those who are considered Christians reaches 2000; but their Shamanism is still retained, hardly anything being borrowed from Christianity beyond the worship of St Nicholas, who is a most popular saint among them.