At first, medical men judged him to be in the first stages of dementia, but the course of the symptoms and certain biological and psychic data obtained from the examination led them to the conclusion that the case was one of simulation by a morally insane individual. In the first place, the patient's look expressed a certain amount of confusion and constant distrust; furthermore, it was noticed that the filthy, indecent, and cruel acts practised by him were committed only when he knew he was being observed. The warders often saw him retire to a quiet spot and vomit all the nauseous substances he had swallowed publicly. As soon as he believed himself to be secure from observation, the usual apathetic look on his face was replaced by one of vivacity and intelligence. In November of the same year, although he had not discarded his air of imbecility, he gave abundant proofs of intelligence. He helped the asylum barber, and showed skill and neatness in the way he soaped the other patients' faces, but if a doctor appeared on the scene, he would daub the soap clumsily in their eyes and mouths. In playing cards he showed no lack of skill and never missed an opportunity of cheating. All these facts pointed to shamming, and the suspicions of medical men were amply confirmed by his escape on the 26th of November. The manner in which he had prepared and executed this plan showed great astuteness on his part. Some time before, he had completely changed his clothes and dressed with a certain amount of elegance. He left a note bidding an affectionate farewell to everyone. Later on, he confessed to a fellow-prisoner that he had prepared everything beforehand for his escape as soon as he should have sufficient money. He also asserted that he had felt pain when pricked. Some of the peculiarities manifested in this case, aphasia, insensibility, and coprophagia, have been noticed in other simulators, and it is easy to see why morally insane persons, who are naturally insensible and filthy in their habits, should adopt these peculiarities as traits of their insanity. The stubborn resistance offered by the subject to all attempts to apply diagnostic instruments, except those for measuring insensibility, may be explained by fear lest the simulation should be detected. Simulators of insanity are generally psycho-physiologically, and often anatomically, degenerate, and their inferiority obliges them to resort to violence and trickery--the traits of savage races--to counter-balance their natural disadvantages. The simulation of insanity resembles in its motive the mimicry of certain insects which assume a protective resemblance to other and noxious species. Naturally inferior individuals tend to imitate characters of a terrifying nature (psychic in this case) which serve to protect them and enable them to compete with others who are better equipped for the battle of life. MENTAL DERANGEMENT AND CRIMINAL MONOMANIA DEMONSTRATED BY THE ANTHROPOLOGICAL EXAMINATION