BY ROBERT T. EDES, M.D. Anomalies of Shape, Size, Number, and Position. The kidneys are two glandular organs, of a concavo-convex shape so characteristic as to be frequently used as a term of comparison, situated on each side of the vertebral column, with the longer diameters nearly parallel thereto, but slightly convergent toward the upper extremity, and extending from about the upper border of the eleventh rib on the left side and the middle of the corresponding rib on the right to the second or third lumbar vertebra. Hence they are somewhat less than half covered by the last two ribs. The upper extremity is a little the wider and the thinner, and by this peculiarity and a recollection of the position of the vessels (from the front, vein, artery, ureter) the two kidneys may be assigned to their proper sides after removal from the body. They are behind, and at their upper extremities nearly in contact with, the peritoneum, resting, with their more or less voluminous envelope of adipose tissue, upon the great muscles of the loins. The fat which in the normal condition surrounds the kidneys varies, as might be supposed, within wide limits, and is by no means devoid of importance, since its deficiency is undoubtedly a predisposing cause for some of the displacements hereafter to be described. In this fatty mass may also be situated perinephritic abscesses, and into it spread with considerable facility morbid growths originating in the kidney itself. At the middle of the inner borders of the kidneys are situated the hiluses into which enter veins, arteries, ureters, nerves, and lymphatics, united by connective tissue and forming a sort of pedicle. The normal weight of each kidney is to be expressed by a rough average as from four and a quarter avoirdupois ounces, or one hundred and twenty grammes, on the one hand, to seven ounces, or two hundred grammes, on the other; but since a deficiency in the size of one is not unfrequently compensated by an increase in the other, it would be safer to give the weight of the pair as from two hundred and forty to four hundred grammes, the lesser number representing those organs which are not only small but anæmic, and the larger those which are either distinctly hypertrophied or much congested: many diseased kidneys will also be found within these limits. The size of the kidney is in a general way proportioned to the size of {20} the body: the proportion is stated as 1 to about 240. A disproportionate change in the size of both kidneys without any change in structure is a true hypertrophy, and may be met with in persons whose habits as regards the ingestion of fluids (especially such as are freely secreted by the kidneys--for instance, beer or other forms of dilute alcohol) tend toward excess, or where a disease like diabetes throws a large amount of diuretic material into the circulation.