The object of this communication is to focus attention on certain interesting facts concerning the mid-gut of the larva of Anopheles subpictus previously reported in outline by us (Dasgupta & Ray, 1954,1955). In the course of our routine examination on Anopheles larvae collected from different parts of the city and its outskirts, we directed our inquiry on certain histochemical problems. Our observation was mainly concentrated on detecting the sites of alkaline phosphatase activity in the mid-gut. Our interest, however, was quickly aroused by the occurrence in the secretory cells of the mid-gut of Feulgen-positive intra-nuclear inclusions. So far as we are aware, inclusion bodies of this nature have never been reported from Diptera.