modifiable, usually precedes Z, m, n^ r, or s and another conso- 

 nant. If this qualification, as characteristic of stem-changing 

 verbs, were accordant with actual facts, it would furnish us a 

 most welcome aid in recognizing by their form these verbs. 

 Unfortunately, however, it is of absolutely no value as a cri- 

 terion in the case considered. In the first place, not much 

 more than one-half of the stem-changing verbs show the form 

 described by Diez, their modifiable vowels being followed by 

 any single consonant except y, A, k^ a?, and by hr^ dr. In the 

 second place,, and what is more fatal, the unmodifiable e^ o 

 are also followed, without any significant distinction as re- 

 gards frequency or combination, unless sporadically, by pre- 

 cisely the same consonants or consonant-groups. A rapid ex- 

 amination of all the verbs under A with an unvaried thematic 

 e^ o shows that these vowels are there followed by the same 

 simple or compound consonants as the stem-changing verbs, 

 and by very few others. And a glance at the 50 verbs quoted 

 in support of the fact that the Latin themetic short c, o very fre- 

 quently remain unchanged under the accent in Spanish verbs, 

 show the same thing. Nor does it appear that there is any 

 other difference of form or phonetic surroundings that can 

 serve as a basis for a broad, practical distinction between the 

 variable and invariable stems. A few distinctions, however, 

 which will serve at least to mark off quite a number of verbs 

 with themetic e, o as not belonging to the stem-changing class 

 should be noticed here. Foremost among these is the impor- 

 tant, and yet apparently unobserved, fact that in a majority of 

 stem-changing verbs it is the radical and not the termination 

 vowel that is modified, while in the other verbs it very fre- 

 quently is the termination vowel, a very large percentage of 

 these verbs having been formed by secondary derivation when 

 the period of vowel gradation had passsed in Spanish. In 

 only 21 stem-changing verbs, most of them ending in -endar, 

 ■entm\ the varied vowel is terminationaP , Farther, the modi- 

 fiable vowel is never in hiatus or followed by any other surd 

 mute than, in a few sporadic cases, c, t\ and, when £-, never 

 ""a Cf. list, p 7. ' 



