136 TESTACEOUS MOLLUSCA. 



which the lateral ones are creuulated, the central flattened. 1^.. 14. 

 — TV. Columbia. — {Like Soleniforme.) 



C. RiNGICULUM. S070. Juu. Z. P. 1840.— C. I. f. 11.-— 

 Ileeve.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. — Vat'. Pale yellow. — Va?\ Tinged 

 with red anteriorly. — Ceylon, 



C. IsLANDicuM. Lin. \\24.—D.p. 128. — Ch.f. 195, 6.—E. t. 

 300. /. 8.— TF. t. 5. /. 21.— Gould. Mas.f. 58.— {Young— G. 

 PuBESCKNS. 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 hnes 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. 

 1 J . . 2. — N. Av^erica, Iceland, ^'c. 



C. PuNCTULATUM. Brod. 8^ Sow. Z. J. 4. — Heeve. 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. 

 l_i \L. 



^C. Nodosum.* Mont. 2). 81.— im. 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. -^ . . -y^Tr. — England. 



C. RiGiDUM. Wood. G. C. t. 57./. 2, S'.—D. p. 126.— W. t. 

 5.f.4l. 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, f . .J. — l7i the Banksian collection. 



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

 \3\.— Turt. B. t. 13. /. 9. p. 185. Oval and oblique, prodixced 

 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, ^..-f-^. 



C. SicuLUM. Sow. Jun. Z. P'. 1841.— C. /. /. 31. Thin, 

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



