Observations of the behaviour of a small macropod marsupial, A. rufescens, were made at night on two males and five females in an enclosure. They were nocturnal and during the day returned to grass nests. Males were extremely aggressive to one another while females were more tolerant of each other. Animals were not active for the entire night. Behavioural patterns that were recorded included posture, gaits, comfort movements, grooming, nest building, feeding, marking behaviour, exploratory behaviour, interactions, vocalizations and sounds, activity rhythm, general reproductive behaviour and homosexual behaviour.

A male specimen of brush-tailed bettong taken near Cairns in north Queensland and attributable to Bettongia tropica Wakefield, 1967, has 22 chromosomes, i.e. 20 autosomes plus X and Y sex chromosomes. The autosomes are seemingly identical in size and shape to those of Bettongia penicillata ogilbyi (Waterhouse). The larger size of X and Y chromosomes in the tropica specimen is due to the presence of extra constitutive heterochromatin (C-banding material). It is concluded that there is no chromosomal basis for the specific distinction currently afforded to the north Queensland brush-tailed bettong.

IN 1982, the Queensland subspecies of the blackfooted rock-wallaby Petrogale lateralis purpureicollis was reported to occur around Mt Isa and south to around Dajarra (Briscoe et al. 1982). During 1991, the known range of this taxon was extended 300 km to the north-west when an adult female P. l. purpureicollis was collected from ?Ridgepole Waterhole? in the Musselbrook Resource Reserve near Lawn Hill National Park (Eldridge et al. 1993). In 1994 the range was further extended when P. l. purpureicollis was recorded from the Constance Ranges and the upper reaches of Stockyard and Elizabeth Creeks; around the town of Cloncurry and the following distances from the town: 85 km north west; 60 and 87 km west; 4, 23, 28 and 35 km south and 15 km east (Bell et al. 1995). Approaches by the Cannington Mining operation to the southwest of McKinley in October 1999 to confirm the presence of rock-wallabies on nearby Glenholme Station established the presence of P. l. purpureicollis; a 75 km range extension to the south-east.