The Collaborative International Dictionary of English v.0.48:

Pterodactyli \Pter`o*dac"ty*li\, n. pl. [NL.] (Paleon.)
   Same as Pterosauria.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Pterosauria \Pter`o*sau"ri*a\, n. pl. [NL.] (Paleon.)
   An extinct order of flying reptiles of the Mesozoic age; the
   pterodactyls; -- called also Pterodactyli, and
   Ornithosauria.
   [1913 Webster]

   Note: The wings were formed, like those of bats, by a
         leathery expansion of the skin, principally supported
         by the greatly enlarged outer or " little" fingers of
         the hands. The American Cretaceous pterodactyls had no
         teeth. See Pteranodontia, and Pterodactyl.
         [1913 Webster]