The Collaborative International Dictionary of English v.0.48:

Talapoin \Tal"a*poin\ (t[a^]l"[.a]*poin), n. (Zool.)
   A small African monkey (Cercopithecus talapoin or
   Miopithecus talapoin) -- called also melarhine.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Cercopithecus talapoin
    n 1: smallest guenon monkey; of swampy central and west African
         forests [syn: talapoin, Cercopithecus talapoin]