An analysis of the present composition of the Josani Forest, Zanzibar is discussed and the status of the forest considered. Particular interest is paid to those species used as food plants by the endemic subspecies of red colobus monkey, Colobus badius kivki Gray.
The forest is shown to have Calophyllum inophyllum L. and a species of Eugenia as co-dominants. The former species is considered likely to be indigenous to Josani, not introduced as presumed by previous authors. A number of species in Josani are found widely distributed on islands in the Indian Ocean, and the relation of Josani Forest to these insular floras is discussed.
It is tentatively suggested that the forest lies partially in a mature solution basin and that this has had an important influence on the present composition of the forest.