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An attempt is made to distinguish components contributing to the variation of a multifactorial character. Digital ridge count in man is a multifactorial character of high heritability. The principal components analysis employed here suggests that there exist several distinguishable arithmetic components, that these components are equatable with meaningful biological components affecting the development of the dermal ridges on various digits, and that these components are identifiable in several populations, but account for different proportions of the variation in each.