Summary Ten of 34 virus strains tested showed significant growth or were sustained in the established cell line derived from the insect Antheraea eucalypti and adapted to grow in the absence of insect hemolymph. All were arboviruses: Japanese encephalitis (two strains), yellow fever, and St. Louis encephalitis (Group B); Cache Valley and Bunyamwera (Bunyamwera group); Ťahyňa, snowshoe hare, and California (California group); Indiana vesicular stomatitis (ungrouped). Bunyamwera virus and those of the California group merely survived or propagated only to low levels, whereas the remaining six increased 3.7 to 6.0 logs beyond amounts inoculated. Cytopathogenic effect was not seen. Viruses failing to propagate in these cultures, or which deteriorated commensurately with cell-free controls, were all members tested of groups A, C, and Tacaribe, six of 10 members of the B group, eight ungrouped arboviruses, and three nonarboviruses. These results indicate that the Antheraea cell line may be a selective substrate for certain viruses, but possible differences among morphologically different cell types, with respect to the pattern of selectivity, remain to be studied in detail.