Morphology of the bidens mosaic virus particle

Electron microscopical observations were made on exudates obtained from plants of Bidrus pilosa, Chenopodium amaranticolor Leonolis nepaetifolia, Helianthus annums. Nicotiana tabucum, Cassia occidentalis, Chenopodium ambrosioides, and Physalis floridona infected with a virus that induces mosaic on the first named species. The presenes of a flexible thread with a normal length 720 mm. x 12-13 mm was recorded in the exudates from the: diseased plants, but not in those from the healthy ones, and is considered to represent the causal virus.