"Skull of <i>Spatularia</i>, with the long beak removed, the anterior (asc) and posterior (psc) semicircular canals exposed; Au, auditory chamber; Or, orbit of eye; N, nasal sac; Hy, hyoidean apparatus; Er, representatives of branchiostegal rays; Op, operculum; Mn, mandible; A, B, suspensorium; D, palatoquadrate cartilage; E, maxilla." &mdash;Whitney, 1889
<p>Illustration of the exposed and labeled skull of a paddle-fish with the long beak removed.

The Skull of a Paddle-Fish with the Beak Removed

"Skull of Spatularia, with the long beak removed, the anterior (asc) and posterior (psc) semicircular…

"Skull of Polyodon. n, nasal cavity; sq, squamosal; mh, hyomandibular; sy, symplectic; pa, palate-pterygold; m, Meckelian cartiledge; mx, maxillary; d, dentary; h, hyoid; op, operculum; br, branchiostergal; s.cl, supraclavicular; p.cl, postclavicular; cl, clavicle; i.cl, infraclavicular." &mdash; Encyclopedia Britannica, 1893

Polyodon

"Skull of Polyodon. n, nasal cavity; sq, squamosal; mh, hyomandibular; sy, symplectic; pa, palate-pterygold;…