leptocardia

Lep`to*car"di*a, n. pl. Etym: [NL., fr. Gr. (Zoöl.) Defn: The lowest class of Vertebrata, including only the Amphioxus. The heart is represented only by a simple pulsating vessel. The blood is colorless; the brain, renal organs, and limbs are wanting, and the backbone is represented only by a simple, unsegmented notochord. See Amphioxus. [Written also Leptocardii.]

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