We have seen that the cancer patient, both in the very earliest stages and during the whole period of the disease, gives evidence of departures from the ideal normal life, and presents functional disorders of various organs, with derangements of metabolism; these point to errors of nutrition, which latter are of significance in connection with the development and continuance of the malignant disease. The conclusion offered was that cancer is a medical affection, due to systemic causes, and that the simple surgical excision of a certain diseased portion cannot be expected to check or remove such a malady, or to prevent recurrence. And this has been abundantly demonstrated by the history of the disease, with its steadily increasing mortality under increasingly active surgical treatment during the last fifteen years, as was shown in my former lectures and will be further illustrated later. Recognizing, then, that cancer is a great and widespread disorder of nutrition, let us consider some of the facts regarding its extension and some of the influences concerned in its production. SEX.—Cancer is much more frequent in females than in males. In the United States Mortality Reports for 1914 there were 31,138 females to 21,282 males; thus, in a total of 52,420 deaths from cancer 59.4 per cent were in females, with a preponderance of 9,856. This excess is largely due to cancer of the breast, from which there were 5,423 deaths, and cancer of the female genital organs, causing 8,152 deaths, of which 7,470 were from cancer of the uterus. The death rate in males, however, seems to be increasing of late years; in the United States in 1912 males formed 39.7 per cent; in 1913, 40.1 per cent; and in 1914, 40.6 per cent. In England, according to Williams, the proportion of males to females is increasing much more rapidly. This greater mortality of males is due to the greater number of deaths from cancer of the stomach and liver, buccal cavity, and skin. In 1914 there were 19,889 deaths from cancer of the stomach and liver, or 37.9 per cent of the whole number; of these 10,122 were in males to 9,767 in females, or an excess of 355 males, whereas in 1912 the females were 87 in excess. In the United States the cancer death rate for males has increased since 1901 31.8 per cent and for females 25.3 per cent. AGE.—Carcinoma is exceedingly rare under 20 years of age, most malignant tumors at that period being sarcomata. After 25 the number of deaths from cancer about doubles each five years up to 40, and then increases steadily, until the actually greatest number of deaths, 6,909 (3,071 males, 3,838 females), occurred between 60 and 64 years of age, after which they decreased steadily; there were 267 deaths at 90 and over, 8 of them being 100 years and over. At no period did the deaths of males exceed that of females, and from 35 to 39 years of age the latter were almost three times that of males.