FAMILY AURICULIADjE — AURICULA. 57 



FAMILY AURICULIADjE. 



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 ? 



Obs. This small family corresponds with the Auriculaces 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. Rdssel, Essex Jour. Nat. Hist. Vol. 1, p. 67. 

 A. id. Gould, 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 striae. 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, 3. Height, - 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 — Part 6. 8 



