REPR OD UCTION. 927 



Puberty. By puberty is meant the period of sexual maturity, at which 

 the individual becomes able to reproduce. In the male the exact time of its 

 onset, characterized primarily by the appearance of fully ripe spermatozoa, is 

 not well known, but is believed to be about one year later than in the female. 

 In temperate climates, therefore, it usually appears in boys not before the age 

 of fifteen ; it is earlier in warmer regions. It is preceded and accompanied by 

 acceleration in bodily growth, already spoken of. Other bodily changes, such 

 as general maturation of the functions of the reproductive organs, alterations in 

 the bodily proportions, increase of strength, and growth of the beard, all of which 

 are elements of the transformation from boyhood to manhood, either occur at 

 that time or follow soon after. One of the most obvious external changes is 

 that of the voice. Its tone may fall permanently an octave, and for the time being 

 become rough, broken, and uncontrollable. This is due to a sudden general 

 enlargement of the laryngeal cartilages and a lengthening of the vocal cords. 



In the girl the oncoming of puberty is marked more exactly than in the 

 boy by the appearance of menstruation, in the majority of girls in temperate 

 climates at the age of fourteen to seventeen. But other characteristic anatom- 

 ical and physiological changes in the body occur. The uterus, the external 

 reproductive organs, and the breasts become larger, while the pelvis widens. 

 The prepubertal acceleration of growth has been mentioned. Nervous disor- 

 ders are especially prone to make their appearance at this time. The subcuta- 

 neous layer of adipose tissue develops and confers upon the outlines the grace- 

 ful curves characteristic of the woman's body. The mental faculties mature, 

 and the girl becomes a woman earlier and more rapidly than the boy a man. 



Climacteric. From the sixtieth year the power of producing spermato- 

 zoa, and, therefore, the reproductive power of man, begins to wane. It con- 

 tinues, however, in a diminishing degree, even to extreme old age, and there 

 is no recognized period of ending of the male sexual life. 



In woman, on the other hand, the sexual period continues for only thirty 

 to thirty-five years, and the climacteric, menopause, or change of life, marks a 

 definite ending of the power of reproduction. In temperate climates it occurs 

 usually between the ages of forty-four and forty-seven ; in warmer regions it 

 comes early, in colder late. It is earlier in the laboring classes, and later 

 where menstruation has first appeared early. Its most characteristic feature is 

 the cessation of menstruation, which is a gradual process extending over a 

 period of two or three years and characterized by irregularity in the oncoming 

 and the quantity of the flow and by gradual diminution. But the cessation 

 of the menses is but one phenomenon in a long series of changes that pro- 

 foundly affect the whole organism and endanger life. The reproductive organs 

 and the breasts diminish in size, and ovulation ceases. The changes in the 

 pelvic organs are in general the reverse of those occurring at puberty. The 

 organic functions generally are rendered irregular; dyspepsia, palpitation, 

 sweating, and vasomotor changes are frequent ; vertigo, neuralgia, rheuma- 

 tism, and gout are not rare ; a tendency to obesity occurs, though sometimes 

 the reverse ; irritability, fear, hysteria, and melancholia may be present ; the 



