Croupous pneumonia, in the child as in the adult, may be defined as an acute, infectious self-limited disease, having its chief pathologic manifestations in the lungs. In this paper the writer proposes to discuss some of the points in the pathology and symptomatology of the disease.
A.—PATHOLOGY. A clear comprehension of the pathology of the subject necessitates a brief glance at the child's lung in its normal condition. Here, the chief points of difference from the adult lung are as follows: the bronchial tubes are larger, the alveoli smaller, proportionally, than in the adult; the inter-alveolar spaces are more extensive, and more richly supplied with blood vessels; also in the alveolar walls, the blood vessels are seen to be larger and more tortuous, giving to the organ the appearance of the lung of obstructive cardiac diseases. These are the main points of difference between the adult and child lung. Obviously,