Cryptozoon
[ krip-tuh-zoh-on ]
/ ˌkrɪp təˈzoʊ ɒn /
noun
an extinct genus of algae from Precambrian and Cambrian times, forming irregularly hemispherical fossil colonies composed of layers of limy precipitate.
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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019