MACROSTOMATA. MOLLUSCA. VELUTINA. 241 



autumn of 1839, great numbers of them were collected on the 

 shores of Nantucket, some specimens of which were furnished 

 me by T. A. Greene, Esq., of New Bedford. 



FAMILY MACROSTOMATA, LAM. 



Shell ear-shaped, the aperture much dilated, margins disunited posteriorly ; 

 operculum none. 



GENUS VELUTiNA, BLAINV. 



Shell small, thin, sub-globose, composed of two rapidly enlarg- 

 ing volutions ; aperture large, sub-ovate, Up thin, not joined 

 behind ; usually covered with a velvety or powdery epidermis. 



VELUTINA L^EVIGA'TA. 



Shell obliquely ovate, very fragile, consisting principally of the 

 Jast of three whorls; epidermis brown, rising into regular, equidis- 

 tant, spiral folds. 



FIGURE 159. 

 State Coll., No. 125. Soc. Cab., No. 2408. 



Helix Icevigata, LIN. and English authors. DONOVAN ; Brit. Shells, t. 105. Mow- 



TAGU : Test. Brit., 382. 



Helix haliotoidea, FABR. (non Lin.) ; Fauna GramL, No. 387. 

 Bulla velutina, MULLER ; Zool. Dan., iii. t. 101, f. 1 to 4. 

 Velutina capuloidea, BLAINV. ; Malacol., pi. xlii. f. 4. 



Velutina rupicola, CONRAD ; Journ. Jlcad. Nat. Sc., vi. 266, pi. xi. f. 17, 18. 

 Galericulum laevigatum, BROWN ; Conch, of Great Brit., fyc., pi. 38, f. 35, 38. 



Shell obliquely ovate or ear-shaped, very thin and fragile, 

 transparent, flesh-colored, or reddish-white ; whorls three, the 

 last extremely large and distended, the others very small, turned 

 to one side, and partly sunken within the last ; suture distinct ; 

 surface faintly marked with the lines of growth, and covered with 

 a thick, brownish epidermis, which is raised at close and regular 

 intervals into fringe-like ridges revolving round the shell ; aperture 

 ample, rounded-oval ; lip extremely thin, but thickening a little as 

 it rises upon the body of the shell ; the two lips uniting behind by 

 a plate of enamel crossing the body of the shell, which, in mature 

 31 



