a. Masculine: vās, _bondsman_.

b. Neuter: vās, _vessel_.

2. Nouns in -ēs.

a. Masculine: ariēs, _ram_; pariēs, _wall_; pēs, _foot_.

3. Nouns in -is.

a. Masculine: all nouns in -nis and -guis; as, amnis, _river_; Ä«gnis,
_fire_; pānis, _bread_; sanguis, _blood_; unguis, _nail_.

Also--

axis, _axle_. piscis, _fish_.
collis, _hill_. postis, _post_.
fascis, _bundle_. pulvis, _dust_.
lapis, _stone_. orbis, _circle_.
mēnsis, _month_. sentis, _brier_.

4. Nouns in -x.

a. Masculine: apex, _peak_; cōdex, _tree-trunk_; grex, _flock_; imbrex,
_tile_; pollex, _thumb_; vertex, _summit_; calix, _cup_.

5. Nouns in -s preceded by a consonant.

a. Masculine: dēns, _tooth_; fōns, _fountain_; mōns, _mountain_; pōns,
_bridge_.