and comparison populations, including examination of the skin, with color photography of selected lesions; ophthalmological studies including slite lamp observations, visual acuity, and accommodation; growth and development studies in children (less than 20 years of age) including anthropometric studies; BCG records on all subjects over 40 years of age; and other x-ray examinations as deemed necessary. B. Laboratory Examinations Hematological examinations included § complete blood analyses (total white counts, differential, platelet counts by phase microscopy, and hematocrit by the microhematocrit method) done at about weekly intervals. Sera were obtained for total protein determinations by proteinoneter, protein bound iodine, and starch electrophoresis studies. An intestinal parasite survey of the population was carried out by examining the stools of 190 people for ova and parasites. Pooled urines and a few sufficiently large samples from single individuals were obtained from both the exposed and unexposed groups for radio-chemical analyses of ce” and sr, Whole~ body counts with gamma spectroscopy were obtained on board the ship by placing the individuals in a massive steel room with 4-inch thick walls, with the necessary crystals and electronic equipment attached. The steel room was constructed at Brookhaven National Laboratory and was transported to Rongelap via commercial ship and LST, C. Difficulties associated with examinations Several difficulties associated with the examinations of the Marshallese should be mentioned: (1) The language barrier made the examinations difficult since very little English is spoken by the Marshallese. However, sufficient interpreters were available to assist the medical team. oj