BOAS] HANDBOOK OF AMERICAN INDIAN LANGUAGES 431 



Besides combinations with precedent palatal stops, a few others 

 are rigidly avoided. These are Is, l-n, l-Jc^, l-g^, l-x^, s-g^, sJc^. 

 Combinations of t sounds followed by s do not occur, because they 

 unite and form an affricative sound; li occurs only at the begin- 

 ning of words (except in the imitation of the language of a monster), 

 and does not enter into consonantic clusters, y and w are strongly 

 vocalic, and are always followed by vowels, although they may be 

 preceded by consonants, w following a 7c sound is assimilated by 

 it, so that the k sound is pronounced with w position of the lips, as a 

 labio-palatal. 



Clusters of three or more consonants follow the same rules as com- 

 bination of two consonants, so that clusters are possible as long as 

 any two adjoining consonants tolerate each other. We find, for 

 instance, xsd, xsf, x^st, x'^st!, x'dg', nxs, nx'q!, nx's, nsL, nit, nib, mxs, 

 mx's, mx'd, msL, mlts, mlw, Ixl, Ixs, Ixm, IxL, Ix^s, Ix'd, Ix'l, Isd; and 

 of clusters of four consonants, xsdx, mx'st, nx'st. 



§ 4. Euphonic Laws 



There are a considerable number of rules of euphony which govern 

 the sequence of sounds. These become active when two phonetic 

 elements come into contact by composition or by syntactic co-ordi- 

 nation. They are partly ante-active (i. e., working forward) or pro- 

 gressive, parth" retroactive or regressive, partly reciprocal. The ante- 

 active processes include laws of assimilation and of consonantic elision; 

 the retroactive processes consist in the hardening and softening of con- 

 sonants; the reciprocal influence manifests itself in contraction and 

 consonantic assimilation. Since the rules of consonantic combination 

 (§ 3) relate partly to the initial, partly to the terminal consonant of 

 the combination, these changes are apparently partly ante-active, 

 partly retroactive; but since they are founded on the mutual in- 

 fluence of adjoining sounds, they are better treated under the head 

 of reciprocal changes. 



{!) Ante-active Changes 



The u vowels do not admit of a following anterior palatal, which is 

 changed into a palatal with following w, or, as we may say, Tc sounds 

 with I tinge become Tc sounds with u tinge when following a u vowel; 

 or Tc sounds following u vowels are labialized. Posterior palatals, 

 when following a u vowel, also assume a u tinge. 



§4 



