from i-stems end also in ā and ī. The pronominal element -sma makes the locative -smin. Stems in an in the older language often lose the i, and use the bare stem as locative.
j. The ending ām is the locative correspondent to dat. āi and abl.-gen. ās, and is taken under the same circumstances: see above.
k. The vocative (unless by accent: 314) is distinguished from the nominative only in the singular, and not quite always there. In a-stems, it is the unaltered stem, and so also in most consonant-stems; but neuters in an and in may drop the n; and the oldest language has sometimes a vocative in s from stems in nt and ṅs. Stems in ṛ change this to ar. In masc. and fem. i- and u-stems, the case ends respectively in e and o; in neuters, in the same or in i or u. Stems in ā change ā to e; derivative ī and ū are shortened; radical stems in long vowels use the nominative form.
308. Dual. a. The dual has — except so far as the vocative is sometimes distinguished from nominative and accusative by a difference of accent: 314 — only three case-forms: one for nom., accus., and voc.; one for instr., dat. and abl.; and one for gen. and loc.
b. But the pronouns of 1st and 2d person in the older language distinguish five dual cases: see 492 b.
c. The masc. and fem. ending for nom.-accus.-voc. is in the later language usually āu; but instead of this the Veda has prevailingly ā. Stems in ā make the case end in e. Stems in i and u, masc. and fem., lengthen those vowels; and derivative ī in the Veda remains regularly unchanged, though later it adds āu. The neuter ending is only ī; with final a this combines to e.
d. The universal ending for the instr.-dat.-abl. is bhyām, before which final a is made long. In the Veda, it is often to be read as two syllables, bhiām.
e. The universal ending of gen.-loc. is os; before this, a and ā alike become e (ai).
309. Plural. a. In the nominative, the general masculine and feminine ending is as. The old language, however, often makes the case in āsas instead of ās from a-stems, and in a few examples also from ā-stems. From derivative ī-stems, īs instead of yas is the regular and usual Vedic form. Pronominal a-stems make the mas. nom. in e.
b. The neuter ending (which is accusative also) is in general i; and before this the final of a stem is apt to be strengthened, by prolongation of a vowel, or by insertion of a nasal, or by both. But in the Veda the hence resulting forms in āni, īni, ūni are frequently abbreviated by loss of the ni, and sometimes by further shortening of the preceding vowel.
