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The eversible vesicles of the sex pheromone glands consist of three cell types, secreting the cuticle, the duct and the pheromone, respectively. Each pheromone-secreting cell has an end apparatus, bounded by microvilli and lined by a granular mass, that is penetrated by remarkable elongate filaments extending far up into the secretory duct. Vesicles containing secretion or secretion precursors abound. The possible role is discussed of the various organelles in the elaboration and transport of the pheromone.

The copper-accumulating region of the midgut is a mosaic of interstitial and cup-shaped, copper-accumulating cells. The cup of each cuprophilic cell is lined with a highly refractile border of long microvilli except in one strain where it is predominantly lamellar. The nucleus lies basally; the basal plasma membrane is fairly extensively infolded. Cytolysomes are abundant and increase in number with increasing copper content of the diet. The interstitial cells bear short, less regular microvilli and have a less electron-dense cytoplasm. The nucleus is apical, the mitochondria-associated basal membrane is very extensively infolded and cytolysomes are less abundant. Virus-like particles present in nuclei of both cell types increase in number with increasing copper concentration.