Contents Page Introduction Program as defined by contract Program studies on the fundamental effects of radiation upon aquatic animals A. Biological effects of X-rays on invertebrates B. Radiobiological studies on fishes C. X-ray diffraction and electron microscope studies on silver salmon spermatozoa D. Personnel Radiobiological studies of the contamination of Eniwetok and Bikini A. Uptake of fission products by algae 10 B. Food cycling experiments with invertebrates ll C. Radiochemical analyses 13 D. Studies of the Marshall Islands fishes 14 E. Personnel 15 Cooperative studies A. Temperature experiment with chinook salmon 16 B. Chinook salmon experiment--1949 brood year 17 Silver salmon experiment--1951 brood year 19 Cc. Other services Monitoring team 20 Library services 21 Speeches by Applied Fisheries Laboratory staff members 21