A boy of 15 (given to masturbation), studied by Macdonald in America, was similarly hyperæsthetic to the symbols of sexual emotion. "I like amusing myself with my comrades," he told Macdonald, "rolling ourselves into a ball, which gives one a funny kind of warmth. I have a special pleasure in talking about some things. It is the same when the governess kisses me on saying good night or when I lean against her breast. I have that sensation, too, when I see some of the pictures in the comic papers, but only in those representing a woman, as when a young man skating trips up a girl so that her clothes are raised a little. When I read how a man saved a young girl from drowning, so that they swam together, I had the same sensation. Looking at the statues of women in the museum produces the same effect, or when I see naked babies, or when a mother suckles a child. I have often had that sensation when reading novels I ought not to read, or when looking at a new-born calf, or seeing dogs and cows and horses mounting on each other. When I see a girl flirting with a boy, or leaning on his shoulder or with his arm round her waist, I have an erection. It is the same when I see women and little girls in bathing costume, or when boys talk of what their fathers and mothers do together. In the Natural History Museum I often see things which give me that sensation. One day when I read how a man killed a young girl and carried her into a wood and undressed her I had a feeling of enjoyment. When I read of men who were bastards the idea of a woman having a child in that way gives me this sensation. Some dances, and seeing young girls astride a horse, excited me, too, and so in a circus when a woman was shot out of a cannon and her skirts flew in the air. It has no effect on me when I see men naked. Sometimes I enjoy seeing women's underclothes in a shop, or when I see a lady or a girl buying them, especially if they are drawers. When I saw a lady in a dress which buttoned from top to bottom it had more effect on me than seeing underclothes. Seeing dogs coupling gives me more pleasure than looking at pretty women, but less than looking at pretty little girls." In order of increasing intensity he placed the phenomena that affected him thus: The coupling of flies, then of horses, then the sight of women's undergarments, then a boy and a girl flirting, then cows mounting on each other, the statues of women with naked breasts, then contact with the governess's body and breasts, finally coitus. (Arthur Macdonald, _Le Criminel-Type_, pp. 126 et seq.)