a common stage of development. The pedagogic principle would be that it is easier to teach across heterogeneous groups from a differentiated writing system (to a variety in which the contrast has been merged), than the reverse. Students speaking the less differentiated variety need only learn to ignore the "superfluous" distinctions as heterographic homonyms, rather than memorizing numerous, seemingly random heterophonic homographs. References Bibliography Herzog, George. "Drum Signaling in a West African Tribe," Word 1:217-38, 1945. Reprinted in: Language in Culture and Society, pp. 312–23. Ed. Dell Hymes. New York, 1964. Herzog, George, and Charles G. Blooah. Jabo Proverbs from Liberia: Maxims in the Life of a Native Tribe. London, Pub. for the International Institute of African Languages & Cultures by Oxford University Press, H. Milford, 1936. Ingemann, Frances, and John Duitsman. "A Survey of Grebo Dialects in Liberia," Liberian Studies Journal, 7(2):121–131, 1976. Joseph Greenberg, The Languages of Africa. Indiana Univ. Press, 1966. Hasselbring, Sue and Eric Johnson. A sociolinguistic survey of the Grebo language area of Liberia. SIL Electronic Survey Reports 2002-074, 2002. Online version: . Sapir, Edward. "Notes on the Gweabo Language of Liberia," Language, 7:30-41, 1931. Sapir, Edward, With Charles G. Blooah. "Some Gweabo Proverbs," Africa, 2:183-185, 1929. Trubetskoy, Nikolai S.Grundzüge der Phonologie. [Principles of Phonology]. Travaux du Cercle Linguistique de Prague, 7. Prague, 1939. WPA Federal Writers' Project, Life History Manuscripts from the Folklore Project, 1936-1940. Online version: Library of Congress American Life Histories: Manuscripts from the Federal Writers' Project, 1936 - 1940, Item 27 of 312 (Nebraska), "Charles Blooah" . Languages of Liberia Grebo languages