~ 27 - The average disintegration rate of this isotope in the four algae was approximately twice that found in four species of land plants as based on disintegration rate per gram of material. Another species of algae (Caulerpa) at Vera Island rr =_— contained about one and one-half times as much wiS5 as did two species of land plants from the same island. Because wi85 was found in the marine algae, other samples of marine organisms from Fniwetok lagoon also were examined for this isotope. The giant clam (Tridacna gigas) is known to concentrate anions in the visceral mass (Lowman unpublished); therefore, samples of Tridacna visceral mass were collected September 27, was known to be present. 1958,.at Vera Island where wis The results of ion-exchange chemical separations on this organ are shown in Tables 2 and 3. yi8s was not present but two other anion radioelements were found -- Ry203+106_p,103+106 (270,000 d/m/e dry weight, 72 per cent of total activity and Zr95-Nb95 (82,000 d/m/g dry weight, 22 per cent of total activity). In addition to the anions, isotopes of the transition element cobalt were present in small amounts (co!, one per cent; C038, 5 per cent; C060 , trace). In a dogtooth tuna (Gymnosarda nuda) sample taken from Eniwetok lagoon on June 22, however, wiss was found in low level in the spleen (11,000 d/m/g dry weight, 4 per cent of