The kidneys, being glands with internal secretion, must then stand in close relation to the other ductless glands, according to the law established by us in our previous works. As already mentioned, we have shown in a communication to the Paris Biological Society, February 25, 1907, that these glands have an intimate relation to the thyroid gland, and _vice versâ_. Thus, alterations of the thyroid always produce changes in the condition of the kidneys. These alterations in the kidneys may, however, not necessarily be based on the intimate relations between thyroid and kidneys as ductless glands, but may be produced by the fact that, when the thyroid is degenerated and cannot destroy toxic products, these poisonous matters will be thrown on the kidneys (the skin and intestines not being of assistance under such conditions) and eliminated by them. Naturally the passage of such poisonous products through the kidneys is liable to produce changes in them, and albuminuria and hyaline or granular casts may show themselves in consequence. The same may also happen after changes in the liver. When this important organ is not able to destroy poisons they are carried in increased quantities to the kidneys, whence their passage will produce albuminuria and hyaline and granular casts, as has been especially described by such French authorities as Huchard, Teissier of Lyons, Molière and Gouget, etc., as occurring in diseases of both liver and gall-ducts. The appearance of albuminuria, and even of hyaline casts, must be taken as a proof of an abnormal condition of the kidneys, and this notwithstanding numerous authorities who are inclined to regard such an occurrence in a more lenient way. We hold, with Professor Senator, that the permanent presence of such elements in the urine is the proof of the fact that the kidneys are not in a normal condition. Even the orthostatic albuminuria of quite healthy persons, which, as its name implies, only occurs when such persons have been standing for a time in an upright position, has been considered by Senator as an expression of the existence of certain changes in the kidneys. According to Senator, the hyaline casts also are not such an innocuous symptom as certain authorities claim, but they are formed from the degeneration of the convoluted tubules. This is the most important element of the kidneys, for the greater part of the solids and toxins are excreted by its cells from the blood, and besides this function these epithelial cells also have an internal secretion. The appearance, therefore, of hyaline casts (which, as Senator found, could be proved under the microscope as having been formed through degeneration of the epithelial cells) must be considered as evidence of the loss of the secreting portion of the kidneys and of the destruction of their most important elements, and can be found regularly in all the toxic processes that take place in the