the allies_.

Exceptions to Gender in the Second Declension.

26. 1. The following nouns in -us are Feminine by exception:--

a) Names of towns, islands, trees--according to the general rule laid
down in § 15, 2; also some names of countries; as Aegyptus, _Egypt_.

b) Five special words,--

alvus, _belly_;
carbasus, _flax_;
colus, _distaff_;
humus, _ground_;
vannus, _winnowing-fan_.

c) A few Greek Feminines; as,--

atomus, _atom_;
diphthongus, _diphthong_.

2. The following nouns in -us are Neuter:--

pelagus, _sea_;
vīrus, _poison_;
vulgus, _crowd_.

Greek Nouns of the Second Declension.