Eighteen (but possibly 20) of 33 and 19 of 32 known or suspected arboviruses from Queensland and New Guinea multiplied after feeding to wild-caught Culex (Culex) annulirostris Skuse and Aedes (Ochlerotatus) vigilax (Skuse), respectively. The strains used of Sindbis, Ross River, Murray Valley encephalitis, Kunjin and Sepik viruses, all of medical importance, multiplied in both species; on the other hand, bovine ephemeral fever virus, of veterinary importance, gave some twidence of multiplication in C. annulirostris only. This study substantiates the importance of C. annulirostris as a vector, and emphasizes the need for further investigation of Ae. vigilax.