PUBERTY, the period in both male and female marked by functional development of the generative system. This period, when capacity for reproduction begins, is indicated in both sexes by certain characteristic signs. In the male puberty is generally reached, in temperate climates, between the ages of 15 and 18, and although it is commonly believed to be reached somewhat earlier in warm regions, climatic con ditions appear to affect the male less than the female. Before the attainment of this period the physical powers have been appropriated to the nutrition of the body. This is in accordance with a well-known law of physiology, whereby the processes of nutrition and reproduction ate mutually antithetic; the reproductive energies are opposed to the nutritive, and act as an im portant drain upon the physical and nutritive powers. Therefore the (generative instincts are limited or restrained until nutrition and growth have been duly advanced.
In the male the occurrence of puberty is marked by a varied and general change in the physical constitution. The body attains, within a comparatively short period, a large relative in crease in size. The form acquires greater ful ness and stamina. The larynx particularly en larges; the voice deepens; there is a growth of hair upon the face, the pubes, etc.; and the
entire sexual system receives an unwonted stim ulus, the testes secreting the seminal fluid char acteristic of full sexual vigor. The male thus reaches sexual maturity. In ordinary cases his virile powers decrease after the age of 50 or 60, when the energies seem to be withdrawn from the reproductive function in the interest of nu trition.
In the female the state of puberty usually begins, in temperate climates, between the 14th and 16th years. At this period the female form acquires a characteristic fulness and roundness. The breasts enlarge, depositions of fat taking place in the mamma and on the pubes, and over the body generally. The internal organs of generation also enlarge, and their functional perfection in woman is marked by the most unequivocal of the signs of puberty, the appear ance of menstruation (q.v.). The production of ova, ready for fertilization, is the most essential and significant sign of the full attainment at once of puberty and of the true female generative functions. (See OVARY). Puberty in both man and woman may be retarded or advanced by in dividual and inherited peculiarities of constitu tion and by modifying circumstances and habits of life.