Seton rock shelter (350 59' S, 1370 03' E) is located in the southwest of Kangaroo Island, South Australia. Excavation of the late Pleistocene deposit in the rock shelter has provided a rich assemblage of mammal, bird and reptile remains dating from more than 16 000 BP to about 10 000 BP. Analysis of these remains shows that the late Pleistocene fauna of Kangaroo Island was more extensive than the depauperate island fauna of today. The disappearance of many species reflects a reduction in open vegetation probably due to a combination of climatic change, the separation of the island postglacially by rising sea level, and the disappearance of a human population within the last 5000 years. The deposit also provides evidence for the contemporaneity of man and one of the extinct Pleistocene kangaroos, Sthenurus cf. gilli, at 16 000 BP.

The occurrence of Antecaridina lauensis in a small freshwater pool on Uipi Island, New Georgia, Solomon Islands, is recorded, and certain morphological features are described to amplify previous descriptions. The ability of the species to live in salt water is considered a significant factor in explaining its presently wide and extremely disjunctive distribution on remote islands. It is suggested that passive ocean dispersal is the method of distribution.

Female brush-tailed bettongs, Bettongia penicillata, were housed with either an intact or vasectomized male or isolated from males in the peripartum period. Development of the quiescent corpus luteum formed at the post partum oestrus was initiated by removing the pouch young. Blood samples for analysis of plasma progesterone were collected from the females 2 days before removal of pouch young, daily for 5 or 6 days and then 2-3 times each week until 19 days after removal of pouch young. Plasma progesterone profiles were similar in pregnant and nonpregnant cycles. There was an early progesterone peak (1206 +/- 121 pg ml-1, mean +/- SEM; n = 16) between days 2 and 5 after removal of pouch young, and a second period of high concentrations (greater than 800 pg ml-1) before birth on day 17.4 +/- 0.2 (n = 16). The interval between the early peak and birth was 14 or 15 days. On five of 34 occasions, no increases in plasma progesterone concentrations occurred after removal of pouch young. On 12 of 15 occasions for 13 females that had been isolated from males post partum, plasma progesterone concentrations also remained low (less than 100 pg ml-1) and did not change after removal of pouch young. Females that showed no increases in plasma progesterone concentration after removal of pouch young had significantly lower (P less than 0.001) plasma progesterone concentrations while lactating than those females that did undergo a cycle after removal of pouch young (60 +/- 4 pg ml-1, n = 17 and 225 +/- 23 pg ml-1, n = 30, respectively). Females isolated from males post partum, and monitored until day 12 after removal of the pouch young, and that showed no increases in progesterone in this period, had ovaries that contained no corpus luteum, only corpora albicantia and numerous atretic or developing follicles. We conclude that brush-tailed bettongs are induced ovulators, a characteristic described for only one other marsupial, Monodelphis domestica, from South America.

Summary. Injection of hcg into mature, female S. crassicaudata induced ovulation in three of six animals, whereas injection of pmsg or of pmsg followed after 48 hr by hcg induced ovulation in all of seventeen females. Seven mated but none littered.Ten adult females were injected with pmsg and hcg at the end of an induced oestrous cycle, when the corpora lutea were degenerate. Six mated but none littered. Of eight young females injected with pmsg and hcg, four mated but again none littered. All ova recovered after induced ovulation were unfertilized.The number of ova released at induced ovulation was higher than in untreated animals and many unruptured follicles became luteinized. Ova were retained in the oviducts for longer than normal.

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