In their volume Tumours of Bone, Geschickter and Copeland describe 65 cases of Ewing sarcoma, of which only one occurred in the ribs. The inference might be that such a location is rare, but we are inclined to believe that the rarity is only apparent, since no less than 4 instances have been observed in our own small material. These cases seem to merit description, more especially as they throw a certain amount of light on the clinical features and pathology of the growth.