DURING dissections of an immature male specimen of the desert locust, Schistocerca gregaria (Forskal), a yellowish larva of Nemestrinidae was found feeding on the testes and the surrounding adipose tissue. It was 1 cm. long. Its posterior end was surrounded by a chitinous cup leading to a slender respiratory tube c. 2 cm. long, which Was constricted transversally along its whole length (these constrictions disappear when pressed during the preparation). The respiratory tube went longitudinally along the midgut and then was bent at right-angles towards the spiracle of the first abdominal segment. The tube was more or less uniform in width, becoming dilated at the cup surrounding the posterior spiracle of the larva. The end of the tube entered the meeting place of the tracheae, which was considerably expanded. The chitin of this end was blackish-brown, due to pathological changes.