June 13, 1958
Dr. Allyn H. Seymour
Marine Biologist
Division of Biology and Medicine
United States Atomic Energy Commission
Washington 25, D. C.
Dear Al:
Enclosed please find a tabulation of the results of strontium-90
determinations of land crab skeletons (Birgus latro) collected in
March 1958 at Rongelap Atoll. The results of previous analyses
are included for convenience in making comparisons. There continues to be a wide range at any particular island. This appears to
be primarily due to individual variability in the specimens collected.
As a further check on the source of variability, analysee are
being made of the carapace as compared to the legs and claws from
the same specimens.
Virtually 100 per cent of the beta-activity in the akeleton is due
to strontium-90 plus yttrium-90. The average percentage in twelve
skeleton and five carapace samples is 100.3 with a range of 94.1
to 106 and a standard deviation of 3.3.
The results of strontium-90 analyses of other tissues of land
crabs will be sent to you shortly,
Sincerely yours,
Edward E. Held
Assistant Research Professor
EEH: mb
cc: Dr. Robert Conard
Dr. Allyn Seymour
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