"There is an interesting correlation of the source of first ejaculation and the age of onset of ejaculation. For the boys who become adolescent by 11 years of age, masturbation provides the first ejaculation in nearly three-quarters of the cases (71.6 per cent); but for the boys who become adolescent last, masturbation is the source of the first outlet in only half of the cases (52.1 per cent). Nocturnal dreams, on the contrary, are the first source for only 21.6 per cent of the younger adolescent boys, but for 37.1 per cent of the late adolescent males. The boys who mature first more often act deliberately in going after their first outlet; the boys who mature last more often depend upon the involuntary reactions which bring nocturnal emissions."