Ām'bu-lā'crā, n. pl.
n. pl. [Lat. ambulacrum, an alley.] (Nat. Hist.) Prominences or perforations in the shell of the Echinus, or sea-urchin, from which extend the tentacles or spines used for prehension or locomotion. Dana.
n. pl. [Lat. ambulacrum, an alley.] (Nat. Hist.) Prominences or perforations in the shell of the Echinus, or sea-urchin, from which extend the tentacles or spines used for prehension or locomotion. Dana.