We thank Dr. Kenneth Glander of Duke University for helpful advice in making our survey. We also extend our gratitude to Deciderio Marichi and Alejandro Guzmán, for expert assistance in camp and field works during the census. This survey was sponsored by the Proyecto Peruano de Primatologia "Manuel Moro Sommo" and was financed by the Peruvian Government and the Pan American Health Organization with funds from the letter of understanding ICF/ZNS/010.
REFERENCES
Aquino, R.; Encarnación, F. Population structure of Aotus nancymai (Cebidae: Primate) in Peruvian Amazon lowland forests. AMERICAN JOURNAL OF PRIMATOLOGY 11(l):17,1986a.
Aquino, R.; Encarnación, F. Characteristics and use of sleeping sites in Aotus (Cebidae: Primates) in the Amazonian lowland of Peru. AMERICAN JOURNAL OF PRIMATOLOGY 11(4):319331,1986b.
Encarnación, F. Introducción a la flora y vegetación de la Amazonia Peruana: Terminologia y descripción de las formaciones vegetales de la llanura amazónica. CANDOLLEA 40:237252,1985.
Freese, C.; Heltne, P.; Castro, N.; Whitesides, G. Patterns and determinants of monkey densities in Peru and Bolivia, with notes on distributions. INTERNATIONAL JOURNAL OF PRIMATOLOGY 3:5390,1982.
Green, K.M. Primates censusing in Northern Colombia. A comparison of two techniques.PRIMATES 19:537550,1978.
Heltne, P.G. CENSUS OF AOTUS IN THE NORTH OF COLUMBIA. REPORT ON PAHO PROYECT AMRO 3171. Washington, D.C., PAHO, 1977.
Hershkovitz, P. Two new species of nightmonkeys, Genus Aotus (Cebidae, Platyr rhini): A preliminary report on Aotus taxonomy. AMERICAN JOURNAL OF PRIMATOLOGY 4:209243,1983.
Ma, N.S.F.; Aquino, F.; Collins, W. Two new karyotypes in the Peruvian owl monkeys (Aotus trivirgatus). AMERICAN JOURNAL OF PRIMATOLOGY 9:333341,1985.
Malleux, O.J. MAPA FORESTAL DEL PERU. MAPA Y MEMORIA EXPLICATIVA. Lima, Departamento de Manejo Forestal, Universidad Nacional Agraria de la Molina, 1975.
Rathbun, G.; Gache, M. Ecological survey of the night monkeys, Aotus trivirgatus, in Formosa Province, Argentina. PRIMATES 21:211219, 1980.
Soini, P.; Moya, L. INFORME SOBRE LOS RESULTADOS DE LOS ESTUDIOS PRIMATOLÓGICOS EN LA ZONA NORTE DE LA ISLA IQUITOS. Iquitos, Report of Ministerio De Agricultura, Zona Agraria VIII, 1976.
Southwick, Cadigan, F. Population studies of Malaysian Primates. PRIMATES 13:118, 1972.
Wright, P. Home range, activity pattern, and agonistic encounters of a group of night monkeys (Aotus trivirgatus) in Peru. FOLIA PRIMATOLOGICA (BASEL) 29:4355, 1978.
Wright, P. THE COST AND BENEFITS OF NOCTURNALITY FOR AOTUS TRIVIR GATUS (THE NIGHT MONKEYS). Ann Arbor, Michigan, University Microfilm In ternational, 1985.
