Primary malignant tumors of bone have always constituted an interesting chapter in pathology. While much uncertainty still exists as regards their causation, a considerable amount of knowledge has accumulated regarding their classification, life history and mode of spread. The chapter seemed almost complete in 1913 when Fischer1added, in connection with a lesion of the tibia, a type of neoplasm previously known to exist only in the jaws and in the region of the pituitary gland. It was with some trepidation that Fischer pictured his tumor as an adamantinoma of the tibia, but since that time 14 additional records of cases have attested the accuracy of his original observation. Many of these later examples have supplied important details regarding the possible causation, histogenesis, mode of extension and ultimate prognosis of this rare malady. Literature on the subject is replete with excellent reviews, by Richter,2Baker and Hawksley,3