White-headed langur  (Trachypithecus poliocephalus)

Folivorous: Leaf eating.
Inbreeding depression: The decreased vigour in terms of growth, survival or fertility that follows one or more generations of interbreeding between closely related individuals.
Karst formation: An area of irregular limestone in which erosion has produced sinkholes, underground streams, and caverns.
Sacculated: Formed with or having sac-like expansions
Subspecies: A population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.

1. IUCN Red List (September, 2008)
   http://www.iucnredlist.org
   
2. Richardson, M. (2006) Pers. Comm.
   
3. Cat Ba Langur Conservation Project (April, 2006)
   http://www.catbalangur.org
   
4. The Primata (April, 2006)
   http://www.theprimata.com/trachypithecus_poliocephalus.html
   
5. Mittermeier, R.A., Valladares-Pádua, C., Rylands, A.B., Eudey, A.A., Butynski, T.M., Ganzhorn, J.U., Kormos, R., Aguiar, J.M. and Walker, S. (2005) Primates in Peril: The World's 25 Most Endangered Primates 2004–2006. IUCN/SSC Primate Specialist Group (PSG), International Primatological Society (IPS), and Conservation International (CI), Arlington, VA. Available at:
   http://www.gibboncenter.org/images/PDF/Top%2025%20Endangered%20Primates%20-%20Final%20Report.pdf
   
6. International Primatological Society (April, 2006)
   http://www.ips2004.unito.it/index.html
   
7. BirdLife Indochina – Cat Ba National Park (April, 2006)
   http://birdlifeindochina.org/source_book/pdf/3%20Red%20River%20Delta/Cat%20Ba.pdf