Under the term "Bright's disease" have been included at various times nearly all forms of chronic kidney lesion. Recent observers have made a general classification which is now accepted by most writers as practical and as nearly correct as our knowledge of the underlying pathology will permit. The first of these in frequency of occurrence is known as chronic parenchymatous nephritis; the second as chronic interstitial nephritis. The first is exudative, and in its development induces a condition of the kidney which is known as the large, white kidney. The second is devoid of exudation and is known as the small, red kidney. Furthermore, the first of these develops in the parenchyma of the organ, and the latter in the connective or interstitial tissue.