This paper will explore and summarize some of the published evidence for the systematic relationships of the colobine monkeys in the poorly known genus, Rhinopithecus. Rhinopithecus comprises four allopatric colobine species (or subspecies, see Groves, 1970, and below) that share a distinctive, turquoise-colored face and nose, the nose being characterized by a sharply upturned superior border with accessory flaps of skin, on the lateral nasal borders, that partially cover the nasal openings (Dollman, 1912; Milne-Edwards, 1870, 1872 [cited in Szalay & Delson, 1979]; Thomas, 1903). Their ecology and distribution will be briefly reviewed and an account of the history of their proposed taxonomic relations will be presented. Some locomotor characteristics of these monkeys will be (very briefly) evaluated to elucidate the relative primitiveness or
specialization of these distinctive monkeys with respect to the eucatarrhine condition and other fossil and living forms
