lua may well be a matter of sampling. One such sample col- lected from each of the two stations differed by a factor of less than three, while the maximum and minimum specific activities of a series of nine sea cucumber guts taken from an area of less than one thousand square feet at Asraanbiru differed by a factor of more than six. The average values of all invertebrate samples from each station are given in Table 9. The limited usefulness of these values is discussed on page 17. They were not considered in the ranking of stations discussed in the preceding paragraph. Table 9 - RADIOACTIVITY OF ALL POST TEST INVERTEBRATE SAMPLES COUNTED AT EACH COLLECTING STATION Thousands of d/m/g Wet Sample Japtan Igurin Max. O.47 75. Min. 0 0 Ave. 0.083 4.0 Rigili 4OO. 0.35 A, Bogallua Engebi Aaraanbiru 7,700. 15,000. £25. 10. 1,200. 1,700. Tissue and Organ Differences. 6,800. 2.1 1,100. Runit 160. 0.63 26. General statements can be made as to tissue and organ differences in specific activity although there were not sufficient specimens of any one species of invertebrates to warrant statistical analysis. The relative rankings presented here are based on comparison of the specifie activity of each tissue or organ in individual specimens. ~ 4o -