SummaryThe basis for, and advantages of, the use of sequence analysis of proteins are presented. Cytochrome c is used as an example and it is suggested that not enough work has been. done upon the amino acid sequences of proteins of fungi, especially cytochrome c. Other means of studying proteins and enzymes in order to acquire data useful to evolutionists who deal with fungi are discussed, including analysis of mechanisms of control of enzyme activity, electrophoretic migration and properties of enzymes such as response to activators and inhibitors, pH and temperature optima etc. Finally, micromolecules are discussed in the context of their function in the fungi, and suggestions are made as to their present and potential use in phylogenetic studies of these organisms.