dibranchiata

Century Dictionary and Cyclopedia

1. An order of acetabuliferous cephalopods, containing the decapod and octopod Cephalopoda. It is one of the prime divisions of Cephalopoda (the other being Tetrabranchiata), having two gills in the mantle-cavity, from 8 to 10 arms bearing suckers, a complete infundibulum or funnel, and usually an ink-bag, with, or more frequently without, a shell. (See cut under ink-bag.) All the living cephalopods, excepting the pearly nautilus, belong to the Dibranchiata, such as cuttlefishes, squids, calamaries, etc., together with the paper-nautilus. (See cuts under argonaut and Argonautidæ.) Belemnites are fossil forms of the order. The order is generally divided into two suborders, Octopoda or Octocera, and Decapoda or Decacera. Also called Cryptodibranchiata. See also cuts under belemnite and cuttlefish.

GNU Webster's 1913

1. n. (Zoöl.) An order of cephalopods which includes those with two gills, an apparatus for emitting an inky fluid, and either eight or ten cephalic arms bearing suckers or hooks, as the octopi and squids. See cephalopoda.

WordNet 3.0

1. n. comprising all living cephalopods except the family Nautilidae: the orders Octopoda (octopuses) and Decapoda (squids and cuttlefish)