A detailed description of the yeast species Arxula adeninivorans (syn. Trichosporon adeninovorans) was given. The yeast assimilated all the sugars, polyalcohols and organic acids used in the conventional carbon compound assimilation test rapidly, except for L-rhamnose, inulin, lactose, lactate and methanol. As nitrogen sources served all conventionally used compounds except creatine and creatinine. Several nitrogenous compounds, e.g. amino acids, purine derivatives, served as sole source of carbon, nitrogen and energy. This was also true of many primary n-alkylamines and terminal diamines, but of nitrogen-less analogous compounds such as alcohols, dialcohols, carboxylic acids and dicarboxylic acids only intermediates of general metabolism were assimilated. For observing growth at the expense of potentially toxic compounds the slant culture method was developed. In this test lactate was readily assimilated but proved to be toxic at the same time. Several aliphatic organic acids and their esters supported growth in this test, as was the case with several benzene compounds such as hydroquinone, 3- and 4-hydroxybenzoic acid, protocatechuic, gentisic, gallic and ferulic acids, 4-hydroxyacetophenone and 1-phenyl-n-dodecane.