Crime in general in temperate climates tends to reach its maximum at the beginning of the hot season, usually in June.  Thus, in Belgium, the minimum is in February; the maximum in June, thence gradually diminishing (Lentz, Bulletin Societe Medecine Mentale Belgique, March, 1901).  In France, Lacassagne has summated the data extending over more than 40 years, and finds that for all crimes June is the maximum month, the minimum being reached in November.  He also gives the figures for each class of crime separately, and every crime is found to have its own yearly curve.  Poisonings show a chief maximum in May, with slow fall and a minor climax in December; assassinations have a February and a November climax.  Parricides culminate in May-June, and in October (Lacassagne’s tables are given by Laurent, Les Habitues des Prisons de Paris, Ch. 1).

Notwithstanding the general tendency for crime to reach its maximum in the first hot month (a tendency not necessarily due to the direct influence of heat), we also find, when we consider the statistics of crime generally (including sexual crime), that there is another tendency for minor climaxes in spring and autumn.  Thus, in Italy, Penta, taking the statistics of nearly four thousand crimes (murder, highway robbery, and sexual offences), found the maximum in the first summer months, but there were also minor climaxes in spring and in August and September (Penta, Rivista Mensile di Psichiatria, 1899).  In nearly all Europe (as is shown by a diagram given by Lombroso and Laschi, at the end of the first volume of Le Crime Politique), while the chief climaxes occur about July, there is, in most countries, a distinct tendency to spring (usually about March) and autumn (September and November) climaxes, though they rarely rise as high as the July climax.

If we consider the separate periodicity of sexual offences, we find that they follow the rule for crimes generally, and usually show a chief maximum in early summer.  Aschaffenburg finds that the annual periodicity of the sexual impulse appears more strongly marked the more abnormal its manifestations, which he places in the following order of increasing periodicity:  conceptions in marriage, conceptions out of marriage, offences against decency, rape, assaults on children (Centralblatt fuer Nervenheilkunde, January, 1903).  In France, rapes and offences against modesty are most numerous in May, June, and July, as Villerme, Lacassagne, and others have shown.  Villerme, investigating 1,000 such cases, found a gradual ascent in frequency (only slightly broken in March) to a maximum in June (oscillating between May and July, when the years are considered separately), and then a gradual descent to a minimum in December.  Legludic gives, for the 159 cases he had investigated, a table showing a small February-March climax, and a large June-August maximum, the minimum being