Sadists become experts in the art of assassination without discovery. The cynicism with which some of them have described their sensations shows their cold indifference toward the tragic and the horrible. Krafft-Ebing describes a series of atrocious types of this kind, and unfortunately the press and the criminal law courts continually give us fresh examples. Some sadists assassinate children, others men, when their perversion is complicated with pederasty or sexual inversion. (The story of Bluebeard is probably based on the successive crimes of a sadic.) Sadists do not always confine their attacks to living people; some of them are _necrophiles_, who violate dead bodies and cut them in pieces: others again kill animals, whose sufferings and blood serve to satisfy their desires. Some sadists satisfy themselves by flogging prostitutes or pricking them till they bleed, while others prefer to martyrize their victims slowly, and thus procure the maximum of pleasure. Others again are contented with scenes symbolical of servitude, in which women are compelled to adore and supplicate them, etc. The humiliation of women takes part in the sadist appetite of man and often degenerates into fetichism. Simple imagination in which he plays the part of a tyrant, and which are complicated with onanism or normal coitus, often suffice to satisfy the sadist. Some sadists soil themselves with the excrements of the woman they "love!" When sadism assumes the character of a symbol or a fetich, seminal ejaculation and sensation generally occur without contact with the woman's body. Sadism is more common in men, but occurs also in women. Messalina and Catherine de Médici are historical examples. The latter had her maids of honor flogged before her eyes, and said she was bathing in roses when she witnessed the massacre of the Huguenots. Women in whom sadism takes a milder form are contented with biting a man till he bleeds, during coitus. Sadism appears to be most often an effect of hereditary alcoholic blastophthoria. (B). _Masochism_ (association of sexual desire with submission to cruelty and violence). The term masochism is applied by Krafft-Ebing to a form of sexual perversion described by Sacher-Masoch in several of his romances. Masochism is exactly the converse of sadism. The desire of the masochist is excited by humiliation, submission, and even blows; the pain he feels when he is flogged gives him intense pleasure. Like sadism, this perversion may be incomplete. When it is complete the masochist is affected with psychic impotence and is incapable of normal coitus. Ill-treatment and humiliation are alone capable of causing him erections, seminal ejaculations and pleasure. However, comedies representing his humiliation, or corresponding efforts of his imagination may succeed in replacing the reality and procure the desired effect.