LAMELLARIA. 337 



Lamellaria perspicua. 



Fig. 158. 



Shell obliquely-ovate, pellucid, white, compressed ; aperture very large ; spire 

 minute and lateral. 



Helix perspicua, Lin. Syst. Nat. 12th cd. p. 12.50. 



ILlix haliotoidcn, LiN. Syst. Nat. 1250. — Martini, Conch, i. t. 16, fig. 151. 



Bulla hnliotoidea, MoNTAGU, Test. Brit. 211, pL 7, fig. 6, and vign. 2, fig. 6. — Maton 

 and Rackktt, Lin. Trans, viii. 123. — Brown, Encyc. Brit. vi. 462. — Wood, In- 

 dex, pi. 18, fig. 61. 



Sigaretus haliotoideus, Lam. An. sans Vert. 1st ed. vi. 208. — Fleming, Ediii. Encyc. vii. 

 66; Bi-it. Anim. .360. — BiiowN, Conch, of Great Brit. &c. pi. 44, figs. 1, 2. — 

 Gould, Inv. 1st ed. 244, fig. 158. 



Orijnoeglahra, Couthouy, Bost. Journ. Nat. Hist. ii. 90, pi. 3, fig. 16. 



Lamellaria perspicua, Stimpson, Shells of New England, 44. 



Marsenina Groenlandica, Stimpson, Check Lists, 5. 



Shell small, obliquely-ovate, thin, pellucid, white, smooth and 

 shining ; lines of growth very faint ; whorls two, the first, situated 

 towards one side, is a mere nucleus for the last, which 



pjcr 607- 



otherwise constitutes the whole shell ; aperture nearly 

 the whole area of the shell ; outer lip sharp, entire, and 

 somewhat expanded ; inner lip sharp, with the edge a ^ 

 little turned, regularly curved in conformity to the left 

 outline of the shell, and, entering the cavity of the spire, is seen to 

 terminate there ; in the other direction, the curvature suddenly 

 ceases, and, forming a slight angle, goes onward to join the outer 

 lip ; a thin plate of enamel connects the two lips above. Length, 

 half an inch ; breadth, two fifths of an inch. 



Several specimens of this shell have been found, all of them in 

 the stomachs of fishes. They are about equal in size, l)ut vary 

 somewhat in shape and convexity. The shell is precisely the same 

 as the European one bearing the above name. 



As it is not certain that its entire animal has yet been seen, its 

 genus remains undetermined. Mr. Couthouy rejects the genus Sig- 

 aretus, because, from what he saw of the animal, he judged the shell 

 to be external, and adopted the genus Oxynoe of Rafinesque, with 

 which no one has any acquaintance except its author, and no char- 

 acters are given of its shell except that it is exterior and buUa-form. 

 It seems better, therefore, to leave it where the conformation of the 

 shell would place it, and where others have arranged it, until its 

 animal is fully known, and its place determined. It will most prob- 

 ably be found to belong to the genus Coriocella. 

 22 



