[*] 34. Many nouns may be either masculine or feminine, according to the sex of the object. These are said to be of Common Gender: as, exsul, exile; bōs, ox or cow; parēns, parent.
[*] Note.--Several names of animals have a grammatical gender, independent of sex. These are called epicene. Thus lepus, hare, is always masculine, and vulpēs, fox, is always feminine.