Summary Leveis of netivity: of the plankton for the eastern lagoon 1, were s mmled nine vines in 1364-58. The first observed level dua Marea 26, 1954, 25 davs after detonation of "Bravo" at Bikini, %i8, oxmressed in microcuries per kilogram of planktonic asn, WJC. Fy caid-December 1954, Ceteber i755, to 6. 1% nad decline to 50, about and by late Fallout fror the Redwing series raised the Sulv Jf Level to apprexinately 100. In July 1957 levels were Scill betneen 15 and 260, but ty euirty March 1958, had declined to u.d. Vallout from tne MNur'taex series raised August 1958 lovels so only 0.2 -4 ucfee aca, Tue cecline rave, and Heordtuck, two peaks following Redwing was steep -3.5. ne dutz for the veurs 1254-57, cc %y S discrecariing tae but includli; their later residual effects, a tiape of uf ee Nn With the list observation. it was shown that results weve ne .rly twice as consistent when cased upon ash as upon wet welsht, ang that there wis no significant difference in activity between sumoles taken with fine and coarse meshed nets. 4, On tne aan welgnt basis, tne levels in 1955 at Atlinginae Atoll were no aluner tnan at Ronselap Atoll, whereas they were higher on 4, 7 the veo veight basis. eciy sloves of pre-Redving samoles ranged from -1.6 to -2.4, wnile tne decline slope for the lagoon as a whole over this period viS -*.6, so tnhut tne decline was more rapid than the decay. DO® ARCHIVES