…a burrowing wormlike marine animal of shallow waters. Its body consists of a proboscis, a collar, and a long trunk with gill slits, and contains a notochordlike structure…
…an extinct marine invertebrate animal of the Paleozoic era, forming mainly planktonic colonies and believed to be related to the pterobranchs…
…a marine invertebrate of the phylum Hemichordata; an acorn worm…
…a minute tube-dwelling colonial acorn worm found chiefly in deep water…
