ABSTRACT
Karantgan is the name given by the natives of Borneo to any accumulation of material deposited in the bed of a river by running water. The accumulation of transported material is often subjected to other influences than those caused by the winding of the river, which may create other kinds of karangans. A karangan consisting of fine sand or mud is always overgrown with reeds on the inner edge, or the strip where at high water the shore would be. These reed borders are not found in the karangans of the upper course. Just as in the upper- or middle course of a river any local factor retarding the current creates a karangan, so a more general retardation, spread over a greater distance, may force a river to deposit all or nearly all the boulders which it carries in a comparatively small area.
