SUMMARYThe external symptoms of a hitherto undescribed leaf‐spot disease of young Lacatan bananas are described. The name ‘eyespot’ is suggested since the mature lesion has a white or grey centre and a narrow, well‐defined, brown border.Drechslera gigantea(Heald&Wolf) Ito was consistently isolated from eyespot lesions and, in pathogenicity tests, conidia of the fungus caused typical spots to develop within 48 hr.Conidia ofD. giganteagerminated after 30–60 min. in a film of water on the leaf surface, one to five germ tubes being produced from each terminal cell. After 12 hr., germ tubes were up to 75 μ long and swollen at the tip into appressorium‐like bodies. Penetration of the host occurred within 24 hr. Similar stages in the infection process were observed on naturally infected leaves. Sometimes, one conidium caused two distinct lesions as a result of bipolar germination and infection.Air‐borne conidia ofD. giganteawere caught by means of a Hirst spore trap. They displayed regular diurnal periodicity, being maximal between 08.00 and 14.00 hr. E.S.T. and practically absent at all other times. Conidia were violently discharged under drying conditions. Highest conidium concentrations were recorded after rain. In the vicinity of the trap, the major source of conidia was Bermuda grass(Cynodon dactylonL.) which was bearing zonate eyespot lesions caused byD. gigantea.This appears to be the first record ofD. giganteain Jamaica. In addition toMusaspp., the grassAnthephora hermaphrodita(L.) Kuntze is now added to Drechsler's host list