An icosahedral virus and an elongated virus were found in herbaceous hosts inoculated with citrus plant material carrying the putative citrus tatter leaf virus (CTLV). The elongated virus particle has been always suspected to be the cause of the disease since they were observed by Semancik and Weathers. Several purification attempts to recover this virus from citrus and herbaceous hosts failed precluding any further physico-chemical, biological or serological studies. The icosahedral virus, on

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... he other hand, was more amenable for purificiation in spite of its apparently extremely low concentration in CTLV infected citrus plants. Purification of this virus was never successful when infected citrus was used as the starting material. However, large amounts of icosahedral particles were obtained after transmitting to cowpea and purification carried out using the primary leaves starting to show local lesions 2 or 3 days after mechanical inoculation. The characteristics of the isometric virus allows its tentative classification in the Cucumovirus group according to its physico-chemical properties. Particles were 28 nm in diameter and the electrophoretic mobility of dsRNA extracted from these particles coincides with that of an isolate of CMV. Attempts to transmit the icosahedral virus to citrus plants using mechanical inoculation, slash inoculation and dodder failed.