Heredity in Health and Mental Disorder: By F. J. Kallmann. (New York: W. W. Norton and Co., 1953. Pp. 315. $6.00.)

In this book F. J. Kallmann presents the results of his extensive investigations into the role of hereditary factors in the causation of mental disease. All the important research carried out over the past seventeen years is here included. The work is divided into three sections. The first two deal respectively with 'Heredity in Relation to Mental Health' and 'Heredity in Relation to Mental Disorder'. In nearly all his investigations Kallmann has employed the method of comparative twin studies. In the first part of the book he not only describes the principles and methods of genetics but also produces an abundance of twin material to support his belief that 'The evidence of the over-all data presented in this first section in support of genetically determined variations in man's adjustive patterns and survival values is sufficient to indicate that human individuality and health are no chance phenomena reflecting only the degree of cultural pressures or the extent of instinctual drives. The capacities for health and adequate adjustment are fundamental biological properties with the common denominator of hereditary potentiality'.

While the second part of the book contains the results of investigations into the part played by heredity in convulsive disorders, neurological diseases, and mental defect, the interest of the psycho-analyst will be drawn to the reports on the functional psychoses. Kallmann has little to say about the psychoneuroses, regretting the difficulties of obtaining sufficient twin material for investigations equal in scope to that found for the psychoses.

Kallmann has observed from his 794 schizophrenic twin pairs that monozygotic twins are concordant for schizophrenia to the extent of 86.2 per cent., but dizygotic twins only 14.6 per cent. This, with other information, has convinced Kallmann that genetic factors are decisive in the predisposition to a schizophrenic illness. He does not believe that a mild attack of or freedom from the psychos