In presenting this group of cases, we have attempted to emphasize the following points:
1. Carcinomatous lesions of the gastro-intestinal tract may metastasize to the skeleton.
2. Such metastatic growths will be discovered less frequently in clinical than in post-mortem examination.
3. The bones of the trunk are more frequently the sites of such metastatic lesions than are other bones.
4. On the basis of our study, we would place the incidence of metastasis to bone at from 0.2 to 0.5 per cent. of all cases of carcinoma of the gastro-intestinal tract, with the highest incidence of such metastasis in cases of carcinoma of the rectum.