The peramelids represented in the Madura Cave deposits are Perameles bougainvillei, Isoodon obesulus, Chaeropus ecaudatus, and Macrotis lagotis. -- Perameles bougainvillei is found in abundance in all stratigraphic units. Specimens from unit 1 (7420 B.P. and younger) show no qualitative differences from those in units 2 through 4-5 (15,000-22,000 B.P.). Post-Pleistocene reduction in size is indicated by significant differences in three of nine dental measures tested (P < 0.5, one sided "t" test). -- Chaeropus ecaudatus and Macrotis lagotis are represented in all units and are known from the Nullarbor Plain in historic times. No morphological changes in these species are seen in the period of time represented by the Madura Cave deposits. -- Isodon obesulus is present in all units except unit 7. Its absence from unit 7 is possibly a sampling accident. The recovered specimens are intermediate in size between specimens of I. obesulus from southwestern Australia and Victoria and specimens of I. auratus, but they are closer to the former. No morphological differences are seen between the specimens from unit 4-5 and unit 1. This taxon is not known to have been present on the Nullarbor Plain in historic time. Its presence in early Holocene deposits suggests a change to drier climatic conditions in this region during this time Includes bibliographical references (p. 70-72) The peramelids represented in the Madura Cave deposits are Perameles bougainvillei, Isoodon obesulus, Chaeropus ecaudatus, and Macrotis lagotis. -- Perameles bougainvillei is found in abundance in all stratigraphic units. Specimens from unit 1 (7420 B.P. and younger) show no qualitative differences from those in units 2 through 4-5 (15,000-22,000 B.P.). Post-Pleistocene reduction in size is indicated by significant differences in three of nine dental measures tested (P < 0.5, one sided "t" test). -- Chaeropus ecaudatus and Macrotis lagotis are represented in all units and are known from the Nullarbor Plain in historic times. No morphological changes in these species are seen in the period of time represented by the Madura Cave deposits. -- Isodon obesulus is present in all units except unit 7. Its absence from unit 7 is possibly a sampling accident. The recovered specimens are intermediate in size between specimens of I. obesulus from southwestern Australia and Victoria and specimens of I. auratus, but they are closer to the former. No morphological differences are seen between the specimens from unit 4-5 and unit 1. This taxon is not known to have been present on the Nullarbor Plain in historic time. Its presence in early Holocene deposits suggests a change to drier climatic conditions in this region during this time Fieldiana series has been published as Geological Series by Field Columbian Museum (1895-1909) and Field Museum of Natural History (1909-1943), and as Fieldiana: Geology by Chicago Natural History Museum (1945-1966) and Field Museum of Natural History (1966-1978). Fieldiana Geology New Series No. 1 began June 29, 1979