Conidium formation in 5 species of pathogenic hyphomycetous fungi, Sporothrix schenckii, Exophiala salmonis, E. sp., Geotrichum candidum and Microsporum canis were examined using light and scanning electron microscopy. The fungi, grown in pure culture on potato dextrose agar under defined conditions, demonstrated 4 kinds of conidiogenesis. The taxonomic value of the developmental characters in the classification of the Fungi Imperfecti is discussed.