TRIBE MACTRACEA. 37 



abrupt and rounded ; epidermis fibrous ; umbones small and striated : 

 inside somewhat fuscous. 1^. . If-— Philippine.s. 



C. Antilt^arum. Reeve. Z. P. 1841. ^' Ic. f. 8. Ovate-tri- 

 angular scarcely gibbous, thick, anteriorly sub-augulated, posteriorly 

 rounded ; epidermis fibrous : umbones somewhat depressed and 

 slightly undulated : inside rich chocolate brown becoming pale and 

 whitish towards the margin. 2^..3g^. — TF. Indies. 



C. JuBAR. Reeve. Z. P. 1841. ^ Ic. /. 11. Sub-ovate, very 

 inequilateral, gibbous, posterioiiy inclined and rounded, anteriorly 

 arcuated; with brilliant rust coloured expanding rays under a fuscous 

 here and there bruised epidermis, the sides marked with numerous 

 irregular striae ; umbones compressed and plicated : inside white, 

 anteriorly brown. lf..2|^. — TF. Australia. 



C, CoRBULOiDES. Rccve. Z. P. 18-41. ^' Ic.f. 9. Sub-orbi- 

 cular, very gibbous, deeply grooved towards the umbones, epidermis 

 brown ; posteriorly rounded, anteriorly produced and suddenly 

 rostrated. l..lf. 



C. ZiczAC. Reeve. Z. P. 1841. ^ Ic f. 13. Sub-triangular, 

 depressed, yellowish under a thin epidermis, with flexuous rosy 

 linear markings and two interrupted rays ; anteriorly sub-angu- 

 lated, posteriorly shortish and rounded : lunule on each side bril- 

 liantly banded Avith rosy rays: within somewhat rosy. l..l|^. — 

 Philippines. 



C. Triquetra. Reeve. Z. P. 1841. &; Ic. f. 14. Triangular, 

 solid, rosaceous under a thin epidermis, brilliantly painted with 

 deep pink spots, and transversely striated ; sides nearly straight and 

 scarcely rounded ; lunule on each side large, and brilliantly banded 

 with rosy rays : inside rosaceous becoming white towards the finely 

 creuulated margin. %.-^- 



C. Ornata. Reeve. Z. P. 1841. tj- Ic.f. 17.— Mesodesma O. 

 Gray in Grif. Cuv. Triangular, somewhat depressed, anteriorly 

 flexuous and angulated, posteriorly rounded : pale with transverse 

 striae and short longitudinal chesnut linear markings : within white 

 and bi'own, the mara;iu finely crenulated. i. . 1|^. 



C. Undulata. ^Sow. Z. P. \S'i2.— Reeve. Ic.f. 2. Oval, 

 brown spotted with fuscous under a fuscous epidermis; within 

 brown becoming white posteriorly ; the umbones undulated ; the 

 posterior side inclined and I'ounded ; the anterior the longer, acumi- 

 nated and angulated. 14.. 2 J^^. — Central America. 



C. Gibkosa. Srm. ^Z. P. \S32.— Reeve. Ic. f. 1. <j- *%.?• t. 

 44. f. 2. Sub-oval, gibbous, rather pale, under a brown epidermis ; 

 "within whitish but anteriorly brown ; the umbones undulated and 

 compressed ; the posterior side inclined, rounded, with a few short 

 grooves ; the anterior arcuated, elongated, and acuminated. 1 j . . 1 1. 

 — S. America. 



C. Radiata. Sow. Tank. Oaf. t. 1 /. 2.— Reeve, t. U. f. 1. 



