GASTEROPODA. 179 



one of which shows a pecuHarly curved outer Hp, sinuated or deeply cleft near the 

 suture, somewhat in the form of Stylifer astericola. 



It slightly resembles B. hyalina, Turt., but is much smaller, having the volutions 

 more convex, and without the flattened and angulatcd form of the upper part of the 

 volution of that species, nor is the apex so papilliform. 



BuLL^A. Lamarck. 

 Philine. Ascanius. 1772 (ex LovSn). 

 LOBAEIA. Sliill. 1776. 



Gen. Char. Shell ovato-globulous, thin, and fragile, subhyaline or semitransparent 

 in a recent state ; slightly convolute, with a large and open aperture, and expanded 

 outer lip ; spire small, sometimes hidden by the elevation of the outer lip. 



In this genus the mantle is said by M. Deshayes, (second edition Lamarck, Hist. 

 Nat. des An. s. vert., vii, p. 664,) to be exceedingly large, covering the entire shell, 

 and rendering it invisible, and that the animal does not adhere by any muscle of 

 attachment. In some species, however, a deep muscular impression is made, and left 

 near the outer edge, both in the lower and upper part of it, as if the animal had 

 adhered very strongly to its shell. 



1. BuLL^A QUADRATA. S. Wood. Tab. XXI, fig. 9, a — c. 



BuLL-EA auADEATA. S. Wood. Mag. Nat. Hist. p. 461, pi. 7, fig. 1, 1839. 

 Bulla suadkata. S. Wood. Catalogue in An. and Mag. Nat. Hist. p. 460, 1842. 

 Philine scutulum. Loven. Ind. Moll. Scand. p. 9, 1846. 



S. Testa pusilld, apertd, subquadratd, tenui; vertice truncato, subumbilicato ; anfractu 

 laxe convolufo, siq)erne coarctato, striis divergentibus, cateniformibtis ornato ; marline 

 mtegro, in/erne quadrato ; labio refexo, sine umbilico ; aperturd patentismnd. 



Shell minute, thin, and fragile, of a subquadrate form, with a large and expanded 

 outer hp ; vertex truncated ; apex slightly depressed ; volution contracted at the upper 

 part, ornamented with diverging, punctured, or chain-like stria; ; inner lip expanded 

 over the umbilicus ; outer lip sharp ; muscular impression deep and distinct. 



Aoois, = ; diameter, j of an inch. 



Localifi/. Cor. Crag, Sutton. Recent, British Seas. 



I have but one perfect specimen of this shell, which may possibly be the same 

 species as the one recently found and described by M. Loven, in his ' Synopsis of the 

 Scandinavian Mollusca.' The state of preservation of the exterior of my fossil is not 



