Among the plant viruses there are only two groups that share families with verterbrate and invertebrate viruses. They are Reoviridae and Rhabdoviridae. Both are insect-borne plant-pathogenic viruses transmitted in a persistent manner. The characteristics of the virions of wound tumor virus (WTV) and rice dwarf virus (RDV) are known to be double shells of icosahedral symmetry. The structure of RDV was demonstrated in the partially purified preparations as hexagonal particles, 70 nm in diameter with a 40 to 50 nm core. FDV particles in crude gall extracts from Fiji disease infected sugar cane appeared to consist of an inner body about 60 nm in diameter, surrounded by an outer ring with an outside diameter of about 75 nm. Polyacrylarnide gel electrophoresis of the solubilized proteins of purified RDV from rice plants showed the virus to be composed of seven structural polypeptides.