Ultrastructural analysis of peritrophic membrane formation of Drosophila auraria larvae

The cells of the external layer of the proventriculus of Drosophila auraria larvae, which produce the peritrophic membrane are characterized by bears microvilli, polytenic nuclei, large quantities of ribosomes, very well developed rough endoplasmic reticulum and many Golgi complexes. The examined cells present one of the rare exceptions of insect intestinal cells, that form a prominent secretory product. The material of the peritrophic membrane, that gives a positive neutral polysaccharide reaction, is synthesized by the Golgi complex and is transported to the apex of the cells via secretory granules which discharge their contents in the space between adjacent microvilli and in that way they contribute to the peritrophic membrane formation.