Webster's 1828 Dictionary
COLUBER
n.In zoology, a genus of serpents, distinguished by scuta or hard crusts on the belly, and scales on the tail. Under this genus are ranked many species, as the viper, black snake, etc.
Webster's 1913 Dictionary
COLUBER
Col "u *ber, n. Etym: [L., a serpent. ] (Zoöl.)
Defn: A genus of harmless serpents.
Note: Linnæus placed in this genus all serpents, whether venomous or not, whose scales beneath the tail are arranged in pairs; but by modern writers it is greatly restricted.
The Wordsmith Dictionary