The petioles of the fronds of 45 'Jamaica Tall' variety of coconut palm, Cocos nucifera L., two to six years old, were each injected with 0.05-0.1 mCi Na232 PO4 during parts of the dry and rainy periods, January-May, 1979, at two locations in Jamaica. Approximately 10 000 leafhoppers and planthoppers were trapped on or near the injected tress by light, yellow and cone traps. The insects were autoradiographed on X-ray films, and those showing radioactivity were counted by a proportional gas counter. Twenty one species and seven genera showed radioactivity. When insects of the undergrowth were collected by a D-Vac sampler and were caged on highly radioactive leaflets of the coconut palm, 10 species and one genus were identified as feeders. Experimental controls showed that activity was due to ingestion and not to surface contamination. Numbers of radioactive insects of each species collected ranged between 1-26, with their radiation 17-235 cpm, and background 12-38 cpm. Autoradiographic intensity ranged between 1-10 on a given visual scale. Results of the survey are discussed in relation to the study of the vectors of lethal yellowing disease of coconut.