less with distance from shot islands, with the exception of Rigili, and were least to the south and southeast within the atoll. The average increase in all tissues from pre-shot to post shot activity was greatest by far at Bogallua (Fig. 6 and Table 10). Although Engebi and Bogallua were about equidistant from the target center, at the amount of radioactivity in fish tissues Bogallue showed an increase of from 4 to 18 times that of the fish tissues at Engebi. The data indicate that, of the radio- active materials taken into the gut at Engebi or Bogallua, a greater proportion reached the four other tissues bone, liver 4.6 ( muscle, skin, ) of fish at Bogallua than at Engebi. Land Plants The plants collected before and after the shot included 15 species of flowering plants, 4 species of fungi, and 1 species of lichen. Some of the plants were collected at only a few of the stations. eral, <A check list is given in the Appendix. collections were made In gen- in the areas where rat traps were set (p.62), but a few were made along the beach or wherever it was possible to obtain certain of the species. in autoradiography; pressed directly in the field for future use others were preserved for identification. Some plants were Radiological assay of the plants followed the same procedure used for the other organisms. Counts were made on leaves, stems, roots, flowers, and fungi. -~ 597 - . roy fruits,