ASPERGILLI when found in mycologic cultures of the skin and of the nails have long been considered incidental clinic or laboratory contaminants and of no pathogenic significance. However, increasing evidence over the past twenty-five years has led to the realization that species of this genus of the fungi might actually be primary or secondary invaders of the human nail.1 In 1941 one of us (E. S. B.) had the opportunity to investigate a case of primary invasion of the human nail by a species of Aspergillus. In this case each time nail scrapings were cultured they yielded large numbers of colonies of Aspergillus flavus, but no other species of fungus was recovered. It was observed in this case that the infected nail plate had a dull green discoloration in addition to the usual characteristics of onychomycosis, such as thickening, brittleness, vertical striations and crumbling of the