Recent roentgen study of the lymphatic system began with the investigation of edematous legs. The normal radiographic anatomy of the lymph trunks of the upper and lower extremities has been described by Kinmonth et al. (9), Jacobsson and Johansson (8), and Gergely (6), while abnormalities in their number and structure have been reported by Kinmonth and others (9, 1). Although lymphography of the swollen limb has given valuable information that could be added to and correlated with what was previously known or suspected, we have felt for some time that the most worthwhile use of lymphography would be in the study of lymph node disease. We have directed our efforts to contrast radiography of pelvic and abdominal nodes. This area was selected for study because of the frequency of neoplasms of the uterus, bladder, and prostate and their known propensity to metastasize to these nodes. Also, it is an area where nodes, though not necessarily all nodes, can be visualized by an injection technic without surgical exploration of the pelvis and abdomen. The lack of success in determining the presence of early and minimal involvement of these nodes by conventional means is well known. To evaluate change due to disease, the range of normal must first be understood. Gross lesions may be seen on examination of patients with far advanced disease, but in this group node involvement is most readily apparent clinically, and roentgenography is less important. We sought, therefore, to examine the normal and to obtain information on the limits of normal structure and the possibilities of demonstrating early disease. The worth of lymphography would in our opinion depend upon success in the detection of otherwise unsuspected metastases. Our experience with 72 inguinal and pelvic lymphograms in 38 adult normal males is the basis of the present report. The work was performed on volunteers, inmates of the State Penitentiary, Fort Madison, Iowa. A concurrent portion of our study was devoted to the technic of injection of contrast material into the lymph system. Cannulation and injection of a lymph trunk in the foot is tedious, difficult, and time-consuming. It was believed that a simpler technic would expedite all phases of investigation and permit assessment of its worth. The anatomic terminology to be used in this paper follows that of Rouviere (11). The saphena magna system of subcutaneous lymphatics is defined as comprising those lymph vessels which generally accompany the greater saphenous vein and drain into inguinal nodes. The lymphatics of the saphena parva system accompany the lesser saphenous vein and drain into popliteal nodes and thence by efferent trunks to the inguinal nodes. Inguinal nodes occurring bilaterally, both superficial and deep, are those of the groin inferior to the inguinal ligament. The ilio-pelvic node groups are three, occurring bilaterally: external iliac, hypogastric, and common iliac.