GASTEROPODA. 163 



uncertain ; the sinus in the outer lip resembles that of Pleurotomaria. Mr. Gray has 

 placed it among the Haliotidae. 



1. SCISSURELLA CRISPATA. Fl&m. Tab. XV, fig. 13. 



SCISSURELLA CRISPATA. Flem. Hist. Brit. Animals, p. 366, 1828. 



8. Wood. Catalogue 1842. 

 ASPERA (?). Phil. En. Moll. Sic. p. 160, t. 25, fig. 17, 1844. 



Sc. Testa orbicitlato-ovatd, heliciformi, vertice depresso ; anfractibtis tribus, convexis ; 

 in media cingulis duobus transversis instryctis ; longitudinaliter plicatis, plicis elegantissime 

 curvatis, interstitiis transversim striatis. 



Shell orbiculato-ovate, with a depressed apex ; volutions three, convex, and rather 

 tumid, with a double keel in the middle or outermost portion of the volution ; longi- 

 tudinally plicated, with elegantly curved and crispated ridges, between which it is 

 spirally striated. 



Diameter, ^ of an inch. 



Locality. Cor. Crag, Sutton. Recent, Scottish Coast. 



I have unfortunately but one slightly injured specimen, having a part of the outer 

 lip destroyed ; however, what remains corresponds so well with Dr. Fleming's clear 

 and copious description, that I have no hesitation in assigning it to his species. It 

 appears to be rather less elevated in the spire than Sc. aspira, Phil. (En. Moll. Sic. 

 1844, vol. ii, p. 160, t. 25, f. 17), which it otherwise much resembles.* 



EMARGINULA, Lam. 1801. 



EMARGINULDS. Montf. 1810. 



SUBEMARGINULA. Bldinv. 1825. 



HEMITOMA. Swains. 1840. 

 CLYPIDINA. Gray, 1847. 



Gen. Char. Patelliform, conical, or clypeiform; vertex more or less elevated, 

 and curving slightly backwards ; aperture elongato-oval ; anterior margin with a fissure, 

 thickened within ; exterior generally raised and decussated ; muscular impression open 

 in front. 



Several shells, possessing this patelliform character, with a fissure in front for the 

 passage of the water to the branchiae, but differently situated, were placed by Lamarck 



* Since the above was written I regret to say that the specimen, while in the hands of the engraver, 

 was lost. The figure ahove referred to is, I believe, a faithful representation of what it was. 



