Nephroptosis is one of the commonest diseases of mankind or, perhaps it would be better to say, womankind. Keyes,1in his table of frequency, quoting various authors, gives it as between 4 and 56 per cent for all women, and as between 0.5 and 4 per cent for men. A fair average would be about 10 per cent for women and 1 per cent for men. The condition is much commoner in women who weigh under 120 pounds (55 Kg.) than in women who are in excess of that weight. Of the women who have nephroptosis, only one in ten has symptoms referable to it. As has been pointed out many times, nephroptosis is not part of a general visceroptosis. Deming2and Kelly3discuss and emphasize this point. Symptoms are classified under, first, nonsymptomatic nephroptosis; second, symptoms referable to the kidney region, such as discomfort, pressure or