Parasites are recorded from Isoodon obesulus (Shaw) (Queensland, Victoria, South Australia, and Tasmania), I. nauticus Thomas (South Australia), Perameles nasuta Geoffroy (Queensland), and P. gunni Gray (Tasmania). Nematode species described are : Trichostrongy1idae. - Nicollina iota, sp. nov.; Austrostrongylus acinocercus, sp. nov.; Mackerrastrongylus peramelis (Johnston & Mawson) (syn. Filarinema peramelis Johnston & Mawson); Peramelistrongylus skedastos, gen. et sp. nov.; Asymmetracantha tasmaniensis, gen, et sp, nov. Subuluridae. - Labiobulura peramelis (Baylis); L. peragale (Johnston & Mawson); L. baylisi, sp. nov.; L. inglisi, sp. nov. Rhabdiasidae. - Parastrongyloides australis, sp, nov. Trichuridae. - Trichurus peramelis Baylis. Unnamed species are Nicollina sp., Austrostrongylus sp., and Capillaria sp. Notes have been given where possible on the frequency of occurrence of nematodes, and of each species of nematode, in the bandicoots. Some interesting subspecific variation in Peramelistrongylus skedastos and a specific variation in the species of Labiobulura are both linked partly with the geographical range of the host. Further work on a wider range, both geographical and specific, of bandicoots is projected.