The methods used to observe the construction of the brood chamber and rearing of the young by the female Connoce$halus anceps are described. The period of egg laying and the maternal care, essential for the survival of both eggs and brood, were observed and the behaviour of the female during this time is recorded. Two broods were successfully reared to first year adolescent stages in the laboratory. The two embryonic and three adolescent stages are briefly described and their developmental times recorded. Subsequent stages of development are noted by increase in size until sexual maturity is attained in the second year.

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The function of the reproductive accessory glands has not before been investigated. Their prominence arouses interest in their possible function. A preliminary histological, histochemical, and biochemical analysis has been undertaken in order to start to answer this question. No definite conclusions can, however, be made from the results obtained. From evidence accumulated on the behaviour of the sexes and the peaks of secretion production it seems likely that the product of the female glands would be used to coat the eggs with a colleterial substance. The male Geophilomorpha, Scolopendromorpha, and Lithobiomorpha all spin webs on which they place a spermatophore during courtship, and all three groups possess two well developed pairs of accessory glands which may be responsible for the production of web material. The Scutigeromorpha, on the other hand, only possess a single vestigeal pair of glands and do not spin a web. It is suggested that the accessory glands of the male produce web material although this still remains unproven.

The laboratory conditions under which the centipedes were kept and their general behaviour are described. No indication of sexual recognition between adult centipedes was found during studies made of encounters between members of the same or opposite sexes. All displayed the same avoiding reaction on the first encounter and later adopted the defence posture by which fatal attacks were prevented. Where attacks were not successfully countered, biting may or may not be accompanied by injection of poison into the wound. These centipedes are not immune to the poison of their own species, therefore, fatalities and cannibalism can result from aggressive encounters. The mating behaviour of Cormocephalus anceps was witnessed once in early autumn in South Africa. It was preceded by the typical avoiding reaction and defence posture assumed by either sex towards the other, the male being the more dominant. After adopting this posture, a situation which may last a variable length of time, the subsequent stages of mating behaviour were initiated by the male. The courting behaviour could be followed in five sequences which are described in some detail. The problems of sperm transfer faced by the Arthropoda evolving towards a wholly terrestrial existence and the many modes adopted by this group are considered together with the recent knowledge of the modes of sperm transfer employed by the four orders of Chilopoda.

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