The author is more and more impressed with the part that heredity plays in the determination of arterial degeneration. Especially does syphilis in the parents or grandparents leave its stigma in the succeeding generations in the shape of poor arterial tissue which is prone to early degeneration. Recently W. W. Graves has called attention to a malformation of the vertebral border of the scapula which consists in a concavity instead of the normal convexity of the bone. To this malformation he has given the name, scaphoid scapula. He considers this to be but one manifestation of a general lack of development in the individual. He speaks of this maldevelopment as a blight and considers that syphilis in the ancestors is responsible for the condition in the offspring. He finds that even in children, the subjects of the scaphoid scapula, the arteries are very definitely thickened. While confirmation of his observations is lacking, there is no doubt that we must lay the blame for much of the arteriosclerosis in our patients to the poor quality of arterial tissue transmitted by ancestors who have acquired some constitutional disease. It may have been syphilis, it may have been the degeneration produced by alcohol or other drug. We can not ignore the part which heredity plays. The various factors to be considered in the production of the acquired form of arteriosclerosis appear to me to be but contributory factors to a very great extent, the essential and fundamental factor being the quality of arterial tissue with which the individual is endowed. Arteriosclerosis may occur in infants. Cases have been reported of calcification of the arteries in infants and children. The arteriosclerosis may occur without nephritis or rise of blood pressure. Cerebral hemorrhage in a child of two years has been seen. Heredity in these cases plays a most important rôle. In many of the reported cases there was no question of congenital syphilis. Aneurysms, single or multiple, have been found in the arteries of children, and even the pulmonary artery may show sclerotic changes. =Acquired Form= As a rule the cases usually seen belong in this group because it seems as if a connection could be established almost always between one or more of the etiologic factors to be described and the disease. While this apparently is the case, we must never lose sight of the part which the quality of the tissue plays. When we leave this out of our calculations we undoubtedly make many false deductions. When two men of the same age who have been exposed to the same conditions as far as we can learn, are found to have quite different arteries, the one normal, the other thickened, we must postulate congenitally poor tissue on the part of the latter. Such tissue readily becomes diseased following conditions which would very likely have produced no noticeable effect on perfectly normal, healthy tissue. =Hypertension=