Morbid Growths. =Cancer.= Malignant disease of the lungs is by no means frequent, yet we have abundant evidence that cancer in its several forms may be developed in these organs. Colloid cancer, has been usually found more or less infiltrated through the substance of the lungs, while other forms appear in nodules or isolated tumors. It is seldom, perhaps, that cancer exhibits itself as a primary affection of the lungs, the disease first appearing in some other part, and more frequently, it is said, in the bones or testicles; operation for the removal of cancer in these parts being very liable to be followed by an early development of the disease in the lungs or other internal organs. On the other hand, where the cancer is connected with any organ whose veins form a part of the portal system, as the stomach, spleen, pancreas, intestines, etc., the disease does not so frequently extend to the lungs, while in those cases the liver is more liable to become affected. The _encephaloid_ form of cancer, is that more frequently met. It may be connected either with the bronchial glands, when the diseased mass will be mainly confined to the mediastinum, and may consist of bodies varying in size from that of a cherry to that of a large apple, or, the disease may commence directly in the substance of the lungs, the tumor rapidly increasing in size, and crowding the lungs from their normal position. After death, the encephaloid mass may be found compressing the lungs into a very small space. The tumor presents the usual character of this disease, some of the lobules being soft and pulpy, or brain-like, others of a more firm, cheese-like consistence. =Melanosis.= Two forms of melanotic deposits are observed in the lungs: one, _true melanosis_, and frequently associated with encephaloid disease; the other a deposit of carbonaceous matter from coal dust, smoke, etc., which has been inhaled during life, and distinguished as _spurious melanosis_. _True melanosis_ consists in a deposit of a dark pigmentary matter in the substance of the bronchial glands, found at the bifurcation of the trachea, and along the main bronchi. The glands are at the same time enlarged. The coloring matter may be solid, or slightly fluid, or pasty. At the same time the melanotic matter may be infiltrated to some extent into the substance of the lungs, or deposited in cysts within the same. In _spurious melanosis_, the dark carbonaceous matter is diffused more or less through the whole lung, and may be seen distinctly through the pleura. The bronchial mucous membrane is more or less tinged with the same substance, and generally a quantity of black-colored fluid may be expressed from the cut surfaces. =Hydatids.= Acephalocysts or animal hydatids, have not unfrequently been found in the lungs, and in several instances they have been discharged by expectoration.