Since Nocard in 1888 described a sporothrix as the cause of "farcies du boeuf," a variety of clinical conditions affecting man and animals have been ascribed to infection by Nocardia. This group of organisms has been most frequently reported in subcutaneous abscesses, particularly those about the mouth or neck. Many of these cases were, however, apparently actinomycosis, the differential diagnosis being established in many cases by minor morphologic and cultural departures from Actinomyces bovis. Nocardia has frequently been reported as an etiologic factor in cases of pulmonary disease simulating tuberculosis. Several cases of cerebral abscess have been reported. Nocardial infections of the tonsils, intestinal tract, appendix and bronchi have been reported. Infections of the skin apparently are rare. Most numerous, perhaps, are cases of pseudo-actinomycosis and of mycetoma from which some member of the genus Nocardia has been recovered. In 1896, Rosenbach1 isolated Streptothrix from a case of