-Y- on the species of fish. For example, a halfbeak caught the day after shot had comparatively high concentrations of radioactivity in the skin (28% of total) and comparatively low amounts in the bone (1% of total). Presumably the radioactivity in the skin was due to both adsorption and absorption, whereas it had not yet reached the bone so soon after the shot. The average counts for viscera were higher in most fish for the first 100 days than subsequently. Differences in species in which there were 10 or more samples are to be seen in the low concentration of total radioactivity, for example, erately high concentrations in the liver of wrasse, and the mod- in bone and skin of goatfish (see Appendix). Correcting the percent of total activity per tissue from the above table for the tissue welght by using the percentages 8, 63, 18, 2, and 9 as relative values of the total weight of skin, muscle, bone, liver and viscera respectively, one uc of radioactivity would be distributed as follows: Skin Muscle Bone Liver O79 .061 .163 054 Viscera .643 Variation in the Samples The trend or decline in radioactivity fluctuates rather widely, due, in part, to inadequate sampling and in part to actual fluctuations in the amount of radioactivity in the Belle Island area. The downwind, downcurrent position of the island relative to the target area would undoubtedly subject the Belle region to varying amounts of effluent from the target area.