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Sex pheromones isolated from the cuticle of the female tsetse fly, Glossina morsitans morsitans Westwood, release mating behavior in the male fly at ultrashort range or upon contact with baited decoys. Three active components were identified as 15,19-dimethylheptatriacontane, 17,21-dimethylheptatriacontane, and 15,19,23-trimethylheptatriacontane. Chemical and biological comparisons show that the natural and synthetic compounds are identical.

A successful technique for feeding colonies of Glossina morsitans morsitans Westw. and G. austeni Newst. in the absence of living 'hosts is described. Insects are fed through membranes made of silicone rubber or of agar and Parafilm, overlying blood pools poured onto grooved glass plates. The diet employed is fresh pig blood, collected at slaughter, and aseptic procedures are adopted at every stage of diet preparation and presentation. The reproductive performance of these in vitro-fed colonies in terms of adult survival, fecundity, and offspring size, is the same as that of colonies fed on living hosts, when compared over a long period of time. The fact that the technique is successful when used with a diet of pig blood, but is not successful when used with cow blood prepared in the same way, suggests that the technique per se is adequate to elicit a normal feeding response from these tsetse species. The nature of the nutritional superiority of pig blood is not understood.

A rapid decline in receptivity of mated female Glossina morsitans nzorsitans Westwood is shown to depend on both physical and chemical stimuli associated with copulation. Radiolabelling revealed the transfer of substances from the male to the haemolymph of the female during copulation. Implantation of male tissues or their injection as homogenates into virgin females showed the chemical stimulus to come from the male accessory glands. Receptivity decreased in females mated to males with ejaculatory ducts severed or testes removed and also in females which had a glass bead inserted into their uterus and/or the tip of their abdomen covered with wax, suggesting that a physical stimulus inducing refractoriness is provided by distension of the uterus and/or stimulation of their termindial setae. Exposing virgin females to daily short matings in which no male materials were transferred, confirmed this. Receptivity also declined slowly with age in unexposed virgin females. Transfusion of haemolymph from mated females (up to 11 days old) into virgins did not indicate the existence of a haemolymph-borne ovulation-inducing factor; apparently only physical stimuli from mating are involved in the induction of ovulation, and somehow prime the ovarian tissue so that it responds appropriately later when the egg has matured. Whether the stimulus is transmitted to the ovary neurally or hormonally is unknown.