The particles of broad bean wilt virus and three of its strains aggregated in different ways in infected cells of Chenopodium amaranticolor, C.quinoa and Nicotiana clevelandii. Most aggregates were crystals, interlocking networks of partides and sheets of particles rolled into different tubular forms or lying between adjacent mitochondria. One strain induces the formation of tubules consisting of a membrane around a file of particles. These structures are discussed with regard to the current ideas on the relationships between the virus strains.