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the multicellular rudiment of the future notochord and mesoderm; it is located on the surface of the embryo of vertebrate animals at the blastula stage. During the process of gastrulation, the chordamesoderm lines the interior of the ectoderm and induces the formation of the neural plate within the ectoderm. In anamniotes, the chordamesoderm invaginates through the dorsal and lateral labia of the blastopore, except in the case of teleosts, in which there is no true invagination. In amniotes, the cells of the future mesoderm migrate under the ectoderm in the region of the primitive streak. The cells of the future notochord invaginate in the region of the primitive streak’s anterior end, called Hensen’s node. The characteristics of the chordamesoderm are determined before the beginning of cleavage orduring cleavage and are influenced by the cells of the future endoderm.