OFFICIAL USE ONLY percentage of mn? in fish. zn? Unlike localization in the liver of mammals ’ was found distributed fairly uniformly among the tissues. The co? found in clams accounted for the major portion of the activity. (The ability of clams to concentrate c0°° selectively was verified by laboratory experiments.) The ye rcentage of calcium in the ‘Solis that is available to the plants is not known. The Sunshine Units reported are on the basis that all of the calcium is available. This provides a base line until better knowledge is gained but itis recognizedthat the correctvalue for Sunshine Units probably are one to two orders of magnitude higher. ae OFFICIAL USE ONLY