Heavy Construction
The Allen and Greenough is still under construction;
so some links may not work quite the way you would expect.
68.
In Neuters the Nominative is the same as the
stem, with final i changed to e: as, mare, stem mari-. But most nouns[1][Such are animal,
bacchánal, bidental, capital,
cervícal, cubital, lupercal, minútal,
puteal, quadrantal, toral, tribúnal, vectígal; calcar,
cochlear, exemplar, lacúnar, laquear,
lúcar, lúminar, lupánar, palear, pulvínar,
torcular. Cf. the plurals dentália, frontália, genuália,
spónsália; altária, plantária,
speculária, tálária; also many names of
festivals, as, Sáturnália.] in
which the i of the stem is preceded
by
ál or ár lose the final vowel and shorten the
preceding á: as, animal, stem animáli-.[2][Exceptions are augurále, colláre, fócále, návále,
penetrále, rámále, scútále,
tíbiále; alveáre, capilláre,
cochleáre]
a. Neuters in -e,
-al, and -ar have -í in the ablative singular, -ium in the genitive plural, and -ia in the nominative and accusative plural:
as, animal, animálí, -ia,
-ium.