Abstract
A method of feeding leafhoppers on agar to detect microorganisms in their saliva was developed and used with groups of six-spotted leafhoppers, Macrosteles fascifrons (Stål), transmitting aster yellows and groups not transmitting the disease. Mycoplasma-like bodies ranging in size from 30 to 400 mμ were found in the saliva and salivary sheaths of both groups. The structure of the salivary sheaths is described.