A case is described of a corneal abscess of the left eye of a patient, male, 35 years, from which there was found in pure culture a mycotic micro-organism, Exophiala (Wangiella) dermatitidis, determined also in the native preparation from the pus. The patient is feeble-minded, suffers from von Recklinghausen's disease and has an impairment of the immune system (above all the reduction of T lymphocytes).