136 TESTACEOUS MOLLUSCA. 



which the lateral ones are crenulated, the central flattened. 1£.. 1J. 

 —*W. Columbia. — (Like Soleniforme.) 



C. Ringiculum. Sow. Jun. Z. P. 1840.— C. I.f. 11.— 

 Reeve, t. 85. f. 11. Longitudinally oval, small, thin, gaping on 

 both sides ; anteriorly elongated, somewhat sparse ; the posterior 

 ribs narrow and indistinct, the three central ones broad, flattened, 

 at the margin strongly toothed, the ten anterior narrower, slightly 

 elevated, toothed at the margin. — Var. Pale yellow. — Var. Tinged 

 with red anteriorly. — Ceylon, 



C. Islandicum. Lin. 1124.— JD. p. 128. — Ch.f. 195, 6.—E.t. 

 300. /. 8.—W. t. 5. /. 27.— Gould. Mas.f. 58.— (Young— C. 

 Pubescens. Couthouy.) Large, thinnish, anteriorly longer, rather 

 obliquely rounded ovate, tumid, with thirty-six or more three - 

 sided sharp-edged radiating ribs, the intervening furrows rounded 

 and regularly wrinkled by the lines of growth : beaks prominent, 

 almost touching : epidermis yellowish brown, lax, and bristling into 

 a stiff fringe on the sharp edge of the ribs : within straw coloured. 

 If . . 2. — N. America, Iceland, fyc. 



C. Punctulatum. JBrod. fy Sow. Z. J. 4. — Reeve, t. 84. 

 f. 7. — C. I.f. 7. Suborbicular, with twenty-two elevated rounded 

 ribs, the posterior ones, as well as the interstices covered with 

 minute raised dots, the anterior with a slender horny fringe of 

 epidermis on the front edges : marginal teeth large and deeply cut. 

 I 1 # . \i 



± C. Nodosum.* Mont. p. 81.— Lin. Tr. 8. p. 66.— Wood. G. 

 C. p. 212.— Turt. Biv. p. 186. t. 13. /. 8. Orbicular sub- 

 equilateral and rather flat, brown or whitish, very slightly angular 

 anteriorly ; with about twenty-six close set rounded ribs thickly 

 clothed with obtuse round tubercles which project anteriorly into 

 very short spines ; inside white with generally a chesnut anterior 

 stripe extending half way down the shell. -£% . . -f% . — England. 



C. Rigidum. Wood. G. C. t. 57. f. 2, 3.— Z>~. p. 126.— W. t. 

 5.f. 41. Obliquely subcordate, obovate, anteriorly obtusely an- 

 gulated and longer, whitish under a strongly adherent wrinkled 

 epidermis, with not more than twenty-six prominent radiating ribs 

 armed with small deciduous tubercles : inside white, the teeth 

 strong. |- . .4. — Tn the JBanksian collection. 



C. Ovale.* Sow. — C. Elongatum. Mont. p. 82. — D. p. 

 131. — Turt. B.t. 13. /. 9. p. 185. Oval and oblique, produced 

 and a little angular anteriorly, tumid in the middle and sloping to 

 the sides ; pale rufous with some obscure darker anterior spots, 

 twenty-five prickly ribs, the central flattened and separated by a 

 fine line : beaks prominent. J . . -f-^ . 



C. Siculum. Sow. Jun. Z. P. 1841.— C. I.f. 31. Thin, 

 sub-quadrangular, ventricose, posteriorly narrow, anteriorly broad, 



