ment; individuals with supernumerary parts, parts so located that they cannot function, parts uncoordinated; bodies doubled, etc. Where appears the supremacy, the ultimateness of the individual, in these phenomena?
These facts as to the dependence of the characteristics of the individual on its components and on the way they are combined, and the production of non-unified, monstrous, non-viable individuals by many of the combinations formed, fit most awkwardly into a theory of the thoroughgoing unity, supremacy and ultimate causal power of the organism-as-a-whole, and it is perhaps not unintelligible that Ritter conducts a campaign against 'genetics,' which has brought these facts to light. Although he does not deny the facts briefly summarized above, he recognizes them grudgingly and he charges that "this [elementalist] philosophy more than the intrinsic importance of the objective discoveries is what has aroused the imagination and enthusiasm and stimulated the activity of geneticists" (I, p. 20). Twenty-five years ago our knowledge of the laws of heredity was recognized as practically zero; in no field was absence of scientific knowledge more painfully felt. The discovery of the proper method of bringing that immensely important field into science would appear amply sufficient to account for the arousing of enthusiasm and the stimulation of activity, whatever the theoretical bearing of the facts discovered. When a theory finds certain of the established facts unwelcome, it is an indication of the inadequacy of the theory.
Ritter's attitude toward genetics appears somewhat typical of his attitude toward many lines of work not his own; it is perhaps worth while to look into it a moment. Here as elsewhere the book appears to suffer seriously from a failure to grasp clearly the experimental point of view. The extended discussion of genetics is largely devoted to an attack on the theory that the chromosomes alone constitute the "material of inheritance" ; that they are "the bearers of the hereditary qualities"; a theory that may be incorrect, but one the content of which appears to the reviewer so totally misapprehended by Ritter that his arguments have no bearing upon it. The theory means, in the minds of geneticists that support it as well of those that oppose it, that the chromosomes alone contain the substances by the diversities and recombinations of which diverse hereditary characteristics are produced in the different offspring,—while the remainder of the cell, indispensable though it be, plays a
