With a better understanding of psychopathic phenomena, the underlying psychology of criminology becomes more clearly defined. Maladjustment may express itself in an insane outbreak, criminal act, or in an anti-social deed, indeed, in all of them the underlying phenomenon is a psychopathic condition which comes under the realm of abnormal psychology. The large group of criminals SHOULD not be looked upon as a homogenous class, but the individuality of criminal and the type of the delinquent act in reaction to his heredity, mental make-up and environmental influences should be fully considered. Herein lies the great value of Wetzel's and Willmann's Monograph--these authors report three cases in which criminal acts were attributed to abnormal mental life. The first case was that of a young man of twenty-three, who showed a psychopathic personality with tainted heredity on the paternal side. He was subject to convulsive attacks, which were regarded as hysterical and not epileptic. In his intelligence he was above the average. He was engaged to a young woman, and because she refused to marry him, he at first contemplated to take his life, but later shot at her three times without injuring her, and then made an unsuccessful attempt at suicide. His delinquent act was determined not only by his environment, but also by his peculiar type of personality, which was taken into consideration by the court, and on this ground he was acquitted. In the second case, a young man of twenty shot his fiancee through the temporal region, injuring her severely. Soon after committing this act he surrendered himself to the police. He also showed striking evidences of a psychopathic personality with a strong suggestion of epilepsy, but with intact intelligence. He was given to periods of depression and was unstable mentally. He was easily suggestible and his general conduct was not only controlled by environmental influences, but also by his mood. Suicidal ideas and jealousy played a very important role in his mental life; especially they were marked when he began to keep company with the young woman. Although his abnormal constitution was taken into account, nevertheless he was punished by one year's imprisonment. During confinement he attempted suicide, but was unsuccessful. Some time after his release he committed suicide, the cause of which he assigned to an abortion that was induced by his sweetheart.