ABSTRACT Specific activity measurements, radiochemical a ilyses. and hall: life studies were made of the red alga. collected at Eniweto&’Atoll ia Marck, April results of these studies show that this alge Asparagupsis (azifurmis, and May 154 ; The mure than any other tested, concentrated the 1!3! prodeced By the nuclear weap: ne tests at Bikini and Bniwetus Atolls during tie period This alga may prove uerfu: as an indicator of radiuactive fallout from auciear detu- ed os nationge