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Data accumulated on the parent fish following their spawning
in the spring of 1945 are being evaluated.
Mortality, growth and
other radiation syndromes are being analysed.
The data indicates
that Xeray dosages of 1500 and 2500 r are 90% and 100% lethal
respectively in 64 weeks,
Growth in length and weight appears to
be retarded by irradiation of 750 or 100r with definite symptoms
of X-ray damage sean in trout exposed to such. intensities.
Project VI.
Exposure of invertebrates to X~rays,.
On November 16, 1948, the report entitled, "Lethal effects of X-rays
on Marine Amphipods® (U"FL~14), Kelshaw Bonham was submitted to the
Commission
Marine snails, Thais lamellosa, of the two experiments started July 6
and October 20, 1948, survived the month in apparently good condition
except for a control specimen in the second experiment which had
detached from the substratum and remained withdrawn for 3 or 4
weeks.
On November 22 this specimen was sacrificed and was found
to be quiescent, almost moribund, and to have its operculum almost
completely dissolved.
Toward the end of the month, breeding
congregation, behavior and a few abortive egg cases were observed.
Fresh water snails brought October 24, 1948, from the oreek in Richland,
Washington by R. F. Foster, were X-rayed on November 12.
Groups of
8 snails each were given single doses in roentgens of 500, 1000,
2500, 5000, 10000, 20000, 40000, or 80000 at the rate of 500 r per
minute, with 36 control snails.
Four days later on November 16 all