Word Study
leptocardia
CIDE DICTIONARY
leptocardia, n. pl. [NL., fr. Gr. lepto`s small + kardi`a the heart.].
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. [1913 Webster]
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