278 SUBEMARGINULA. 



The E. octoradiata of Sowerby (pi. 29, fig. 4) is probably a form 

 of this species. It is not the octoradiata of Gmelin and authors 

 generally. 



S. AUSTRALIS Quoy & Gaimard. PL 29, figs. 1, 2, 3. 



Shell ovate, conic, inflated, whitish ; radiating ribs alternately 

 thick, rugose, and small ; vertex median, obtuse, recurved. Margin 

 undulating. Length 28, width 20, alt. 18 mill. (Q. & G.) 



Australia. 



E. australis Q. & G. Voy. de 1'Astrol., p. 328, t. 68, f. 11, 12. 

 Sowb., Thes., p. 217, f. 67, 94. 



S. TASMANIA Sowerby. PI. 29, fig. 20. 



Elevated-conical, pale tawny, with distant, large, rugose, alternately 

 smaller radiating ribs ; expanded behind, narrowed in front; fissure 

 short, apex acute, obliquely recurved. The two prominent anterior 

 ribs are not so much produced as in E. australis, while the rib 

 formed by the cicatrix is more so ; the apex is very acute and turned 

 backward slightly on one side. (Sowb.~) 



Tasmania. 



E. tasmanice SOWB. Thes., p. 218, f. 72; Conch. Icon., f. 58. 



Section Clypidina Gray. 



Clypidina GRAY, Syst. dist. moll. B. M. p. 164. A. ADAMS, P. 

 Z. S. 1851, p. 87. 



Internal groove distinct, ending in a short anterior notch ; area 

 within the muscle-scar decorated with a dark figure in the form of 

 a mushroom of the Agaricus type. 



S. RUGOSA Quoy & Gaimard. PI. 64, figs. 39-41; pi. 29, figs. 10, 



11. 



Shell oval, conical, apex subcentral ; sculpture consisting of 13- 

 17 primary ribs, which are narrow, raised, continuing to the apex, 

 each interval occupied by three small riblets ; cancellated by close 

 raised concentric threads which form prickly scales where they 

 cross the radiating ribs. Interior greenish (or white), the area 

 within the muscle-scar dark or outlined with dark green, usually 

 distinctly mushroom- shaped. Length 17 J, width 13, alt. 8-1 mill. 



Australia. 



E. rugosa Q. & G., Voy. de 1'Astrol. Zool. iii, p. 331, t. 68, f. 17, 

 18. SOWB., Thes. p. 219. Clypidina Candida A. AD., P. Z. S. 



