-According to the statistics quoted in the first table, in about 3 per cent, of all cases the stomach exhibits two or more separate growths. The question therefore arises whether they should be regarded as multiple primary cancers, or as examples of primary and secondary growths occurring in the same organ. In about three-fifths of the cases which we have collected the tumours were situated at corresponding spots on the opposed surfaces. Thus, in one instance a malignant ulcer was present on the posterior wall a few inches from the pylorus, and exactly opposite to it there was a fungating mass one inch and a half in diameter, both tumours consisting of spheroidal-celled carcinoma. A similar instance occurred at the cardiac end of the viscus; and Lunn has described a case in which two small medullary tumours situated opposite one another in the pyloric region had caused obstruction to the outlet by their mutual contact. It can usually be observed that one of the tumours is of more recent formation than the other; and since in all our cases they were identical in structure, there is little difficulty in attributing the formation of the second growth to infection by contact. In a second form of multiple cancers, of which Devic and others have recorded examples, two or more are found upon the same surface of the viscus, but separated from one another by healthy mucous membrane. As a rule they all exhibit the same histological features, and their mode of development can either be traced to erratic lymphatic infection, or be explained by the theory of the transplantation of particles detached from the earlier growth. There yet remain, however, certain cases which hardly admit of explanation by the theory of auto-infection. These are characterised by the simultaneous implication of two portions of the stomach, usually the orifices, by cancerous growths, which may even possess a different structure. Thus, in one of our cases the cardiac orifice was found to be almost entirely occluded by a soft spheroidal-celled growth, while the pyloric region was infiltrated with a cylindrical-celled cancer, and Eipley, Maurizio, and Barth have each described primary cancer of the cardiac and pyloric apertures in the same subject. The fact that two or more organs of the body may become affected by cancer at the same time has long been recognised. Clark and J ackson have recorded instances of contemporaneous disease of the uterus and stomach; V. Winiwarter mentions one in which scirrhus of the breast was associated with a cylindrical epithelioma of the jejunum ; and other examples are to be found in the writings of Kauffmann and Beck. Our own series contains two cases of particular interest. In the first a spheroidalcelled cancer of the pylorus coexisted with a cylindrical-celled epithelioma of the rectum, and in the second there were apparently primary growths of different kinds in the bladder, stomach, and sigmoid flexure. While, therefore, it must be conceded that the majority of cases where several growths exist in the stomach may be explained by some theory of auto-infection, there remain a certain number which can only be regarded as examples of multiple primary cancerous tumours.