[494]. Four substantives with stems in -ū- or -v-, grūs, F., crane, gruis; sūs, M., F., sow, swine, suis; bōs, M., F., ox, cow, bovis; and nix, F., snow, nivis, follow the consonant declension; also the genitive Iovis, and the other oblique cases of Iuppiter ([500]). But sūs has in the plural dative and ablative suibus, sūbus, or subus; bōs has in the plural genitive boum or bovum, rarely bovom ([107, c]), and in the dative and ablative bōbus, or oftener būbus; nix has no genitive plural in good writers ([430]): nivium late, once nivum.
SINGULAR CASES.
[495]. (1.) The nominative singular of gender stems in a mute is formed by adding -s to the stem ([422]): as,
rēg-, king, N. rēx ([164], [1]); duc-, leader, N. dux ([135, 1]); custōd-, guard, N. custōs ([171, 5]); aetāt-, age, N. aetās ([171, 5]); caelib-, unmarried, N. caelebs ([54]); mūnicip-, burgher, N. mūniceps. hiem-, winter, the only stem in -m-, N. hiemps ([167]) or hiems, also takes -s.
[496]. (2.) Stems in a continuous consonant, -l-, -n-, -r-, or -s-, and neuters have no nominative suffix ([422], [423]): as,
cōnsul-, consul, N. cōnsul; flāmin-, special priest, N. flāmen; agger-, mound, N. agger; iūr- for iūs-, right, N. iūs.
For cor, heart, see [476]; lacte, lac, milk, [478]; sanguī̆s, blood, [486]; -s in neuter adjectives, [612].
[497]. (a.) Stems in -ōn- drop -n- in the nominative; stems in -in- for -on- drop -n-, and end in -ō: as,
leōn-, lion, N. leō; imāgin- for imāgon-, likeness, N. imāgō.