A structuralist approach in the study of evolution and classification

A survey is given of structuralism as a method that can be applied in the study of evolution and classification. The results of a structuralist approach are illustrated by examples from the laws underlying numerical changes, from the laws underlying changes in the chelicerate life-cycle, and from the laws underlying the evolution of the chelicerate appendages. Suggestions are given for the study of the laws underlying the transformation of form, and some notes are made on structuring forces and the early stages of organic evolution. Some concluding remarks are finally made on deep structure, phylogenetic classification and evolution.