Abstract
Dacylaria constricta, a neurotropic dematiaceous fungal pathogen of poultry, was evaluated for pathogenic potential in mice. Four isolates of D. constricta and two of Scolecobasidium humicola were injected intravenously into groups of mice. Two isolates of a D. constricta group formerly known as Dactylaria gallopava produced signs of central nervous system infection with cerebral microabscesses and death. None of the mice injected with the two remaining isolates of D. constricta from a group formerly known as Scolecobasidium constrictum or with isolates of S. humicola showed any evidence of infection, and none died. Potential pathogenicity can now be added to the previosuly established physiological differences to separate isolates of D. constricta into two distinct groups.