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Probable molluscan fossils have been discovered in the Reed Dolomite, White-Inyo Mountain area, Inyo County, California. They consist of small orthoconic shells with relatively large bilaterally symmetrical protoconch-like initial termini. Some individuals have a 'U-shaped" (in transverse section) internal structure. The fossils occur at least 900 meters below the strata containing the earliest known olenellid trilobites and are therefore considered Precambrian.
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Michael Eugene Taylor (1966) studied this question.
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