IT MAY seem strange that the comparative philology of some of the African, American Indian, Indonesian, and other lesser groups of languages has been more or less satisfactorily accomplished, while the comparative grammar of Sino-Tibetan, which from the point of view of the number of speakers, culture and economic importance ranks second in the world, has hardly begun. A number of difficulties have stood in the way, difficulties to which reference will be made below. But since there seems to be a general misconception of the present status of our knowledge of these languages, even by linguists working within that field, it will perhaps be well to survey just what has been accomplished to date. While most linguists are inclined to agree that the languages frequently grouped under the name Sino-Tibetan are probably related, the opinion has rested in part upon unfamiliarity with what has been accomplished1 and in part upon the general resemblance of the numeral systems of these languages and their monosyllabic and tonal characteristics. Outside of these facts, the supposed relationship rests almost entirely upon a number of comparisons of words in two or more languages,2 the sole criterion for such comparisons being general