FAMILY AURICULIADEZ — AURICULA. 57 
FAMILY AURICULIADA. 
Shell always spiral and variable. Aperture dentate, and always lateral in relation to the 
axis. Animal elongated, with the body distinct from the foot: no mantle: a collar. 
Tentacles two, with the eyes at or near their base. Mouth usually armed with an upper 
tooth opposed to the tongue. Pulmonary cavity and its orifice placed forward. Genera- 
tive organs united or distant. Terrestrial or marine: freshwater ? 
Oss. This small family corresponds with the Auriculacés of Blainville, and the Limno- 
cochlides of Ferussac. 
GENUS AURICULA. Lamarck. 
Shell oval, more or less pointed and elongated, rarely cylindrical. Spire with five or six 
whorls ; the last enveloping the others. Aperture long and narrow, ear-shaped, with two 
or more folds on the pillar. Animal elongated, enlarged in front into a rostrum or snout. 
Tentacles short, cylindrical, gland-shaped above. Eyes placed at the internal base of the 
tentacles, slightly behind. Foot not divided. 
AURICULA BIDENTATA. 
PLATE V. FIGS. 92, 1, 2, 3. 
(STATE COLLECTION.) 
Melampus bidentatus. Say, Jour. Acad, Nat. Sc. Vol. 2, p, 245. 
Auricula cornea, LAMARCK, An. sans vert. Ed. alt. Vol. 8, p. 339. 
A, bidentata. Russet, Essex Jour. Nat. Hist. Vol. 1, p. 67. 
A, id. Goutp, Invertebrata of Massachusetts, p. 197, fig. 130. 
Description. Shell thin, translucent, smooth, broadest about the upper third. Whorls five 
or six, somewhat rounded ; the last forming the largest part of the shell, with minute wrinkles 
and revolving striz. Pillar-lip bidentate: the upper one, which may be considered as a fold, 
is prominent, transverse, and placed below the middle ; the other oblique, not so large, formed 
by the outer lip as it turns within the shell. Outer lip with four or five parallel revolving 
ridges, not attaining the edge of the lip. Spire short and blunt. Aperture long and narrow, 
widest below. 
Color. Dark reddish brown. Animal reddish brown above, beneath paler. Rostrum 
nearly as long as the tentacles, bilobed. Foot transversely bifid. 
Diameter, 0°3. Height, 0°5. 
Var. a. Aperture narrowed beneath, and with 3 4 revolving dark lines. 
This is a common species in the salt marshes about New-York; often observed near the 
salt water, and said to have been found in the interior. ‘They are occasionally submerged, 
but do not appear to live in the water. Found from Vermont to Florida. 
Fauna — Parr 6. 8 
