The present paper deals with the histology and the functions of the cells in the follicular epithelium of the ovarioles from Nasutitermes sp., comparing them with those of syntermes dirus, and also the development of their first differentiation in the middle zone of the germarium passing by seven different regions of the ovariole up to the formation of the chorion. 1. Besides their protective funcion, the follicular cells effect an important role in the transport of substances from the haemolymph into the oozytes during their growing phase. 2. With the end of their nutritive function, the cells change their activity, forming now the chorion. 3. Between some joining cells, we find in the epithelium triangular perforation, which are covered only by the Tunica propria and which allow an immediate transfer of substances form the haemolymph into the oozytes. 4. The interfollicular cells produce a substance similar to that of the Tunica propira. This complex warrants the better conjunction between the components of the ovariole.