This is Volume XV of nineteen in the Abnormal and Clinical Psychology series. The psychiatrist by dealing with the total personality, tends to become a Jack-of-all trades; he measures his patients' body-configuration and their mental abilities; he assesses his patients' electro-encephalographic records and their paintings; he interferes with his patients' cerebral structure and with their set of values, and so forth. Originally published in 1950, this study is a psychiatric one, it was intended for interested nonpsychiatric research workers as well, and in consequence the description of some phenomena had to be out of proportion to others.