Leptocardia
Pronunciation : Lep`to*car"di*a
Part of Speech : n.
Etymology : [NL., fr. Gr. (Zo?l.)
Definition : 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.]
pl.
Source : Webster's Unabridged Dictionary, 1913