Crichton-Browne remarks that children in springtime exhibit restlessness, excitability, perversity, and indisposition to exertion that are not displayed at other times. This condition, sometimes known as "spring fever," has been studied in over a hundred cases, both children and adults, by Kline. The majority of these report a feeling of tiredness, languor, lassitude, sometimes restlessness, sometimes drowsiness. There is often a feeling of suffocation, and a longing for Nature and fresh air and day-dreams, while work seems distasteful and unsatisfactory. Change is felt to be necessary at all costs, and sometimes there is a desire to begin some new plan of life.[161] In both sexes there is frequently a wave of sexual emotion, a longing for love. Kline also found by examination of a very large number of cases that between the ages of four and seventeen it is in spring that running away from home most often occurs. He suggests that this whole group of phenomena may be due to the shifting of the metabolic processes from the ordinary grooves into reproductive channels, and seeks to bring it into connection with the migrations of animals for reproductive purposes.[162] It has long been known that the occurrence of insanity follows an annual curve,[163] and though our knowledge of this curve, being founded on the date of admissions to asylums, cannot be said to be quite precise, it fairly corresponds to the outbreaks of acute insanity. The curve presented in Chart 4 shows the admissions to the London County Council Lunatic Asylums during the years 1893 to 1897 inclusive; I have arranged it in two-month periods, to neutralize unimportant oscillations. In order to show that this curve is not due to local or accidental circumstances, we may turn to France and take a special and chronic form of mental disease: Garnier, in his _Folie à Paris_, presents an almost exactly similar curve of the admissions of cases of general paralysis to the Infirmerie Spéciale at Paris during the years 1886-88 (Chart 5). Both curves alike show a major climax in spring and a minor climax in autumn.