NOTE: Names of Months are properly adjectives, the masculine noun ménsis, month, being understood: as, Iánuárius, January.
a. A few names of Rivers ending in -a (as, Allia), with the Greek names Léthé and Styx, are feminine; others are variable or uncertain.
b. Some names of Mountains are feminine or neuter, taking the gender of their termination: as, Alpes (F.), the Alps; Soracte (N.).