The literature is replete with instances of gross lesions of the bones associated with lymphoid and myeloid leukemia.1 Many of the patients had unusual findings in the blood and an atypical histopathologic picture. The following study presents the roentgenographic features of the changes of the bone which are associated with lymphoid and myeloid leukemia. LYMPHOID LEUKEMIA Since 1917, eighty-six patients with lymphoid leukemia have been treated at the Memorial Hospital. Of this group, six patients (7 per cent) ultimately showed changes of the bones roentgenographically (table). Four of the patients were over 40 years of age. There were four female and two male patients. The duration of the disease prior to demonstrable changes of the bones varied from two months to three years and eight months. Following osseous involvement, one patient (case 4) is living after two years, and three died within one year. Apparently there is no correlation