children fertility was associated with longevity. [Illustration: FIG. 6.--Katherine, Countess of Desmond. Died 1604 at reputed age of 140.] III ONSET OF OLD AGE The onset of old age varies in different countries, and, like the development of puberty, is accelerated by the high temperature of tropical countries. There is also considerable variation in families and individuals of the same race and country; thus while one man may be senile at 60 years of age another is vigorous both in mind and body at 80. The inconstancy of onset depends on the various factors that may play a causal part; old age may be a physiological involution, but too often is a pathological product. When the period of reproductive power (maturity) wanes that of old age begins; in women this is marked by the menopause, the age of 45 years being taken as the limit of fertility, but before this even in the late thirties the spectre of fading attractiveness may upset the matron and lead to the irregularities of the “dangerous age.” For man there is no such index, and the change is so insidious that most of us would expostulate at Stanley Hall’s[36] statement that old age in men begins in the early forties and sooner in women, or less than half-way through the physiological lifetime of a hundred years. According to Dante 45 marks the termination of youth, and it seems generally agreed that as a rule--and every one is entitled to consider himself as the exception-- The gay bloom of fifty passes quickly away And people get fat and infirm and all that. [Illustration: FIG. 7.--Petratsch Zortan, a Hungarian. Reputed to have lived from 1537 to 1724.]