There are no published observations on the effects of sugarcane mosaic virus {SCMV) on the formation of inclusions in sorghum {Sorghum vulgare Pers.) and reports concerning other hosts do not agree fully. HEROI D and WEIBEL (1963) and THOMPSON and THORNBERRY (1968) found virus particles associated with infection of maize {Zea mays L.) with sugarcane mosaic virus, but neither reported the presence of inclusion hodies. Others (L'DWARDSON 1966, KRASS and FORD 1969, GARDNER 1969, SHU-CHEN LIN 1969, LANGENBERG and SHROEDER 1970 observed bundle and pinwheel type of inclusions in leaves of SCMV infected plants, as well as virus particles. THOMP-SON and THORNBKRRY (1968) found virus particles only in yellov/ areas of SCMV mfected maize. GARDNER (1969), however, found no difference in the type or distribution of inclusions between the green and yellow areas of mosaic caused by SCMV in maize.A Johnson grass {Sorghum halepense [L.J Pers.)-mfecting strain of SCMV causes mosaic diseases in maize and sorghum in Australia (PENROSE 1974). Serologica! differences have been detected between American and Australian strains of SCMV (TAYLOR and PARES 1968, SNAZELLE, BANCROFT andULLSTRUP 1971). There are no published observations on the effects of Australian isolates of SCMV on the formation of inclusions in hosts of SCMV. A study was, therefore, made to examine the effects of an Australian isolate of SCMV on the type and location of inclusions associated with SCMV infection of sorghum and maize.