Source : Webster's Revised Unabridged Dictionary (1913)

Siphonata \Si`pho*na"ta\, n. pl. [NL.] (Zo["o]l.)
   A tribe of bivalve mollusks in which the posterior mantle
   border is prolonged into two tubes or siphons. Called also
   {Siphoniata}. See {Siphon}, 2
   (a), and {Quahaug}.

Siphoniata \Si*pho`ni*a"ta\, n. pl. [NL.] (Zo["o]l.)
   Same as {Siphonata}.