oe +6 ’ 4 4 yuysical properties one would expect {t to behave much like strontium and some indication of this is shown in Table 2. It is kuown that the size of fallout particles are related to the distance from the explosion at which the fallout occurs; and that the mean particle size in general decreasas as distauce increases. it is most likely therefore that the particles arriving at Station Y¥ - 3 (80 miles from ground zero) were larger than those arriving at Station Y - 6 (180 miles from ground zero at the time of arrival). However, no direct measurements were made, . . and numerical estimates of particle size require extensive qualification beyond the scope and classification of this paper. me 4 DISCUSSION tentteed In Table 1 it will be noted that each of the classes as well as each type of organism in Sample Y - 6 shows the remarkably similar specific activity when reierred to dry TABLE 2 ANALYSIS AND COMPARISONS Fraction Gross Activity Rare Earths Bal@ sr#¥.¥ ars NbM RW Undetermined Radioohemical Analysis of Separated Fractions of Samples Y - 8, c/min of Beta .ctivity Water* 82,500 3,530 1,780 (410) Solid Fractiont Total on ®t 320,000 97,000 646 402,500 100,530 2,420 (320,000) 1,600 89 _808 1,689 890 840 33,900 39,960 69,300 29,600 74,000 49,980 70,190 29,840 107,900 89,940 (4.5)$ (69,000) : Percent of Total Activity Contributed by Separated Fractions of Sample ¥ + 8 ww Water 20.5 Solld Fraction 79.5 0.88 B41 0.44 6.40 0.16 0.02 0.22 37.2 0.21 7.20 8.43 18.4 : ' 1 3.82 12.43 Ba cee Apparent Specific Concentration Factors of Organic Matertal Over Supernatent Water, (e/min/gm)/(o/min/gm) 780 5,500 70 0 15,000 6,300 440 _ Comparison of the Compositions of the Activity Retained in Two Selected Organiams from Sample { - 8. (Activity given relative to total for each organism, in percent) _ 23.8 0.26 0.47 _ _ _ 75.7 Sagitta (robusta) _ 40.8 1.2 0.60 = = _— 87.4 * Filtered through sintered glass. 1 Solid fraction retained by filter «mostly inorganic rem2ins). PApproximate speciiic activity ¢,min/gm; 1.6. assummag 260 ml supernatent and 1 gram vet plankton in the specimen. a, . . . Copeveds ymixed) ; weight (Column 10); whereas no comparable consistancy appearsin the activities of the components of Sampie Y- 8. This inconsistancy possibly is related to the difference in size of the fallout particles at the two ranges. Becauseof the large variation in size, and presumablythorefore also in food consumption, it is unconvincing to compare activities of individuals of quite different sizes. Amongst the possibie reference parameters in the data, dry weight would appear to offer the best reference for such comparisons as are being p.ade here. However, it is possible that organisms may share activities in the preserving bottle, and if this were true, cried spevimens having properties quite different in life might appear the same in the cry weight basis. This type of sharing is, of course, no legs interesting but obscures the vital effects. Thore appears no wey to avoid this difficulty entirely unless biological classisi~ 15 : 1 .