The Italian criminologist Cesare Lombroso developed the idea that criminal behaviour depended on inherited characteristics, rather than being potentially innate in all humans. Working from anthropometry, the study of racial characteristics through measurement of the body, he proposed a theory of criminal pathology based on an anomaly of the skull which predisposed the subject to deviant social acts.
Lombroso’s argument was that criminal behaviour was a throwback to an earlier evolutionary form of behaviour, and that this would be reflected in the shape of the subject’s head, equally displaying an earlier evolutionary form. In this case, a rapist with a trococephalous head (round, due to the premature union of the frontal and parietal bones of the skull) with long and looping ears, a flattened forehead, slanting and squinting eyes, a snub nose, and enormous jaws, is described as ‘monstrous’ and of a type ‘seldom seen in an asylum’.
Hyde in Robert Louis Stevenson's Strange Case of Dr Jekyll and Mr Hyde is described as ‘monstrous’, but also ‘small’. The gentlemen in the book are unable to describe his features, but are nevertheless convinced that he is ‘deformed’.