Diabetes mellitus is most common in adult life, although Dickinson reports a case at six years which was fatal, Bence Jones a case aged three and a half, and Roberts another three years old; and in the reports of the Registrar-General of England for the years 1851-60 ten deaths under the age of one and thirty-two under the age of three are included. This statement, in view of the experience of the difficulties of diagnosis in children so young, seems almost incredible. I have never myself met a case in a child under twelve years. At this age I have known two, of which one, a boy, passed from under my notice, while the second, a girl, recovered completely. The disease is most common between the ages of thirty and sixty. The oldest patient I have ever had died of the disease at seventy-two years, having been under my observation for three and a half years. It is decidedly more frequent in men than in women, carefully prepared statistics of deaths in Philadelphia during the eleven years from 1870 to 1880, inclusive, giving a total of 206 deaths, of which 124, or three-fifths, were males, and 82, or two-fifths, females. This is the experience of all. My own experience has been singular and interesting. Up to April, 1881, I had never met a case in a woman. Of 18 cases outside of hospital practice which I have noted since that date, 9 were men and 9 women. But I still do not recall an instance of a woman in hospital practice, although I have constantly cases among men. Not much that is accurate can be said of the geographical distribution of the disease. It seems to be more common in England and Scotland than in this country, at least if the statistics of New York and Philadelphia are considered. In the former city, statistics extending over three and a fourth years show that out of 1379 deaths, 1 was caused by diabetes; in Philadelphia, in eleven years, 1 out of 875; in England and Wales, according to Dickinson from observations extending over ten years, 1 out of 632; and in Scotland, 1 out of 916. According to the same authority, the disease is more prevalent in the agricultural counties of England, and of these the cooler ones, Norfolk, Suffolk, Berkshire, and Huntingdon. According to Senator, it is more common in Normandy in France; rare, statistically, in Holland, Russia, Brazil, and the West Indies, while it is common in India, especially in Ceylon, and relatively very frequent in modern times in Wurtemberg and Thuringia. Seegen says it is more {204} frequent among Jews than among Christians, but I have never seen a case in a Hebrew.