What is epithelial mesoderm; a layer of cuboidal epithelium cells, formed from a portion of the mesoderm during the differetiation of the germ layers. It constitutes the boundary of the coelum called?

mesothelium — Epithelial mesoderm; a layer of cuboidal epithelium cells, formed from a portion of the mesoderm during the differetiation of the germ layers. It constitutes the boundary of the coelum. (Webster's 1913.)

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