Twenty-one spp. [Allescheria terrestris, Aspergillus fumigatus, Chaetomium theromophile var. coprophile, C. thermophile var. dissitum, Chrysosporium pruinosum, Humicola grisea var. thermoidea, H. insolens, H. lanuginosa, Malbranchea pulchella var. sulfurea, Mucor miehei, M. pusillus, Myriococcum albomyces, Sporotrichum pulverulentum, S. thermophila, Stilbella thermophila, Talaromyces emersonii, T. thermophilus, Thermoascus aurantiacus, Thermomyces stellatus, Thielavia thermophila and Torula thermophila] of thermophilic and thermotolerant fungi were tested for the ability to degrade cellulose and lignocellulose. Thielavia thermophila is newly described as cellulolytic. Only C. pruinosum and S. pulverulentum were found to degrade lignocellulose extensively. In a number of cases the moisture content of the solid substrate influenced degradation by the species tested.