Normal and immunosuppressed mice and a horse were inoculated intradermally and subcutaneously with suspensions of conidia and hyphae of Culicinomyces sp. A transient local inflammatory reaction developed at the site of inoculation but attempts to reisolate the fungus were unsuccessful. Tortoises, toads and 2 species of lizard were each dosed orally and subcutaneously with a suspension of conidia and hyphae of Culicinomyces sp. Macroscopic and histological examination of selected tissues showed no apparent lesions as a result of oral dosing. Fungal hyphae and conidia were demonstrated at subcutaneous inoculation sites for up to 3 weeks in lizards, 18 days in toads and 10 weeks in tortoises. The fungus was in circumscribed lesions and remained viable for a limited period despite a chronic inflammatory response. Tortoises inoculated orally and subcutaneously with fungal suspension remained healthy for up to 12 months afterwards. At autopsy there was no evidence of fungus at the inoculation site.