The first find of a colony of a Coptotermes species smaller in size than the wellknown C. curvignathus Holmgr., was made while I was inspecting Acacia tomentosa trees growing on the forest boundary near Tanggung, in the teak area east of Semarang, in August 1920. The colony inhabited a deep fissure situated in the fork of a living tree. In the following years what appeared to be the same species was found on dry timber in a few other localities of the same area, and also, by my co-worker F. VERBEEK, in the forests near Randublatung and Tjepu, all in Central Java. In 1926/1927 the first complaints were received of damage done by this termite in a godown in Surabaya, East Java, and to a house at Bogor, West Java. Gradually more evidence came to hand of its not infrequent occurrence in the lowland forests and its occasional invasion of buildings in various parts of the country. In 1934—1937 observations on this Coptotermes were included in a scheme for incidental investigations into the termite life in the teak forests surrounding the field laboratory at Gedangan, near Semarang. Data on the attack on dry and green trunks of certain timbers were collected and a preliminary, rather unsuccessful search was made for the site of the central nest. The species was also included in various experiments. At Bogor some observations could be made concerning its occurrence in buildings and part of a colony was brought to the laboratory. Some results of these investigations have already been published (KALSHOVEN, 1941, 1952, 1955).