comparative Ly Sieh Levels of ope? in the curip:ce probubly represent . condition sof equilibrium with the svziluble sutrontium rather than an uecwaulation over a lone, poerio!t of time. In musele of Lani crabs collected at Belic Islan? in February anc November 1955, 1.37 of 1954, Cs sf ar 30 QO +? » and analyzed in Janusry an? laurel. uh and cot Ayppl 4! at accountes for off, 10%, und i%, respectively, of the total activity. to the exoskeleton, muscle had 2 varlLable, In contrast though generally Yeereasing level of long lived Lsotopes throurmhout the post Nectar collecting period at Belle Island. ‘Whether or not sp? levels in the muscle were decreasing Juring this period te not imown, ilthouch there was a decrease from 90 c/n/e wet in i single specimen collected in Pebruary 1955 to €9 df/g uct in 2 specimen collecte i in November 1355, experience has shun that individual veriation may account for such Jifferences. Values of determinations of sr?? in musele of lanc crabs fron Kabvelile Islan?, Rongclup itoll, indicate that the sr?’ Llovel lc remaining constant. great: But here again indivicual variation 1c the value for duplicate determinations of musele from a single coconut crab collected fn January 1355 wae 5921.5 Afafe wet and the average of three samples of hermit crab musele taken in July 195€ was 59¢37 d/n/e wet. Tt should be clearly understoo! that the ubsve ¢Lseussion applies only to the lant crabs and not to marine crabs. 2 “Marine erubs have lower levels of total activity than Jo the land crubs 90 unm? contain little, if any, Sr Table . 3) o (sec for example NRDL-455