an o : haiti a _' . a) sosait «157%. ee Ogme tee KO : SUMMARY oF OPERATIONS ON CONTRACT NO. ¥-28-094-0ng-33._5 FOR THE MONTH OF SEPTEMBER 1948, “ “\ R * a Project Ie | Basic studies on the effect of X-rays upon fish.yarious in stages of development, Seotions I# and II*. | fhe data summarizing the effect of exposure to 100 r units of es a rays on the ¥ generation of chinook salmon fingerlings is nearing the wages _ final report form, These data will bring up to date the results of the experiment that started in the fall of 1943 with the axposure of adult chinook salmon to X-rays prior to their spawning. Project VI. Exposure of marine invertebrates to X-rays. Marine snails, Thais lamellosa, exposed to X-rays on July 7, 1948 with whole body single doses of from 5900 r to 20,000 r contime under ln observation. > > Sp bo - a - Ef a |e 2 2 a 2 5 og e 2558 fs O BSS 3 |e cana Oo The marine snails in this experiment, alive on July 31, survived | “to the end of September. The failure of exposures to X-rays from the 5900 r — 10,000 r range to cause mortality in excess to the controls suggests that the snails are tolerant of X-rays in the range used. t peat experine Re- LD.a50 mts usingne hi gher dosesdeterming doses areersee OF ENERGY DECLASSIFICATION REVIEW range a F SINGLE REVIEW aie BY: REVIEWER (AOD) Project X. Bikini Resurvey of 1948. waecapa apa DATE: METERRICATIO AciecLeNUMBERS) 2. CLASSIFICAHION CHANGED TO: Z.CONTAINS NO OOE CLASSIFIED INEO COORDINATE WITH: LASSIFICATION CANCELLED—SSSC=«S “CLASSIFIED INFO BRACKETED 7, OTHER (SPECIFY); Of the 2500 ashed samples brought to the Applied Fisheries Laboratory from this summer's field work, 600 were counted during August and the balance during September. In addition approximately 400 samples were *Project and section numbers refer to the Project Ghronoi98 Chart and Summary UWFL-9, revised March 11, 1948. DOS ARCHIVES