ambulacra

1 definition found

ambulacra - Collaborative International Dictionary of English v.0.48 :

  Ambulacrum \Am`bu*la"crum\, n.; pl. Ambulacra. [L., an alley
     or covered way.] (Zool.)
     (a) One of the radical zones of echinoderms, along which run
         the principal nerves, blood vessels, and water tubes.
         These zones usually bear rows of locomotive suckers or
         tentacles, which protrude from regular pores. In star
         fishes they occupy the grooves along the under side of
         the rays.
     (b) One of the suckers on the feet of mites.
         [1913 Webster]