Structure and function of the male sperm ducts and female sperm-storage organs in Aeshna juncea (L.) (Anisoptera: Aeshnidae)

By the use of light and electron microscopy, the micro-anatomy of the 6 genital ducts and the 9 reproductive organs have been surveyed. Sperm bundles transmitted from the testis through the vas deferens become embedded in a carrier jelly and also have additional substances bound to them; obviously the sperm cells are undergoing maturation. In the 2 2, sperm bundles in carrier jelly appear to be deposited in the vaginal canal and, particularly, in the receptaculum seminis, the latter serving for long-term conservation. It seems possible that agents emitted from the posterior accessory glands to the vaginal surface near the genital aperture diffuse forwards, reaching the receptacle entrance. Here they presumably induce a liquefaction of the jelly and break-down of sperm bundles, thus releasing individual sperm cells. Free sperm cells are expected to accumulate in the anterior accessory sacs which they leave during fertilization. The morphological changes taking place in the sperm after transfer to the 9 genital tract appear ambiguous.