SCTJRRIA. 61 



A. lima Rv., Conch. Icon. f. 144, 1855. 

 A. NIMBUS Reeve. PL 35, fig. 30, 31. 



Shell ovate, slightly attenuated anteriorly, rather sharply convex ; 

 apex somewhat anterior ; everywhere decussately wave-striated, the 

 radiating striae being the stronger ; olive, elegantly rayed with faint 

 yellow, purplish around the apex. The rays of this species are very 

 softly expressed, and have more the appearance of rays of light than 

 is presented by any other species, whilst the surface stria? are finely 

 waved throughout, (five.*) 



Habitat unknown- 



P. nimbus RYE., Conch. Icon., f. 143. 

 A. UNCINATA Reeve. PL 33, figs. 91, 92. 



Shell ovate, sharply conoid, apex a little hooked anteriorly; radi- 

 ately profusely finely ridged, interstices obscurely cancellated ; 

 whitish, tessellated or diagonally streaked with blackish-brown ; 

 interior bluish-white, transparent, tessellated and stained with faint 

 chestnut. (Eve.') ^ 



Habitat unknown. 



P. uncinata RVE., Conch. Icon. f. 141. 



Spurious Species. 

 Tectura pusilla Jeffir.=CoccuiJNA. 



Tectura adunca Jeffr.=CoccuLiXA. 



Tectura galeola Jeffr.=CoccuLixA. 



Xacella peltoides Cpr. belongs to SlPHOKABDGDJB. 



Tectura tahitensis and T. radiata PSC.^PATELLA. 



Genus SCURRIA Gray, 1847. 



Scurria GRAY, P. Z. S. 1847, p. 158 ; Guide Syst, Dist. Moll. B. 

 M. p. 171. DALL, Arner. Journ. Conch, vi, p. 262. Not Scurria 

 Cpr. Helcion, Lottia and Acmcea, in part, of authors. 



Shell patelliform. Animal having a branchial plume as in 

 Acmcea, and an accessory branchial cordon extending entirely around 

 the foot, or interrupted in front. Formula of radula 1 (2-l'0'l-2) 1. 



This genus differs from Acmcea in possessing a branchial cordon, 

 like Patella, in addition to the branchial plume. It agrees with 

 Acmcea in dentition (S. mesoleuca, pi. 39, fig. 22). The subgenus 

 Lottia differs from typical Scurria in having the branchial cordon 

 interrupted over the head, but this distinction alone seems scarcely 

 sufficient for generic separation. 



