92 TESTACEOUS MOLLUSCA. 



CYRENA. 



Shell roundish and trigonal ; turgid or ventricose, inequilateral, 

 solid, with a strong epidermis, and the beaks usually decorticated ; 

 hinge with three teeth in each valve ; lateral teeth almost always 

 two, one of which is near the primary ones ; ligament external, 

 and placed on the larger side. 



* Lateral teeth serrated or denticulated. 



C. Trigonella. Lam, 1. Smallish, triangular, sub-equilateral, 

 fulvous and nearly smooth, beaks somewhat violet. \. — E. Indies. 



C. Orientalis. Lam. 2. — Del. t. 7 . f. 8. Transverse, sub- 

 triangularly ovate, olive green, the beaks violet, with transverse dis- 

 tant grooves : violet within, the lateral teeth serrulated, f . — China. 



C. Cor. Lam. 3. — Del. t. 7 . /. 7. — Tellina Fluminalis. 

 Mutter.— D. p. 106.— Ch. f. 320.—E. t. 302. /. 2.— Venus F. 

 W. t. 8./ 1 13. Elongated heart-shaped, oblique, fully as long as 

 broad, anteriorly longer and rather attenuated, thick, tumid, cuticle 

 olive green with often olive brown zones, with distant sub-imbricated 

 grooves : beaks prominent and involute : inside violet. 1 J. — 

 Euphrates. 



C. Fuscata. Lam. 4.— Tellina Fluviatilis. D.p.107. — 

 Ch.f. 321.— E. t.302.f. 2.— Venus F. W. t.S.f.US. Trans- 

 verse, olive green, sub -equilateral, rounded at the sides, not thick, 

 with close sub-imbricated grooves ; beaks obtuse : violet within. 

 1. — Canton. 



C. Fluminea. Lam. 5. — Tellina Fluminea. Gmel. 3243. 

 — D. p. 107.— Ch. f. 322, 3.—Schrce. Fluss. t. 4.f. 2.— Venus 

 F. W. t. S.f. 114. Heart-shaped, gibbous, yellowish-green, girt 

 with transverse broad grooves ; within mottled with white and 

 violet, hinge with the lateral teeth finely denticulated. 1. — China. 



C. Violacea. Lam. 7.— Del. t. 7. f. 5.—E. t. 301./. 1. 

 Ovate elliptic, inequilateral, transversely grooved, violet within and 

 without, indistinctly rayed; anterior side convex and acute, the 

 beaks decorticated ; hinge with the lateral teeth denticulated. 1^. 

 — The figures represent a much larger specimen. — Indian Ocean. 



C. Limosa. Gray. Ann. Phil. 25. — Tellina L. Maton. 

 Lin. T. 10. t. 24. /. 8, 9. 10.— Wood. G. C. t. 46./ 4, 5.— D. 

 p. 106. — JV. t. 5. / 86. Ovate, equivalve, brittle, smooth, trans- 

 versely striated, with a green cuticle and the margin entire ; ura- 

 bones prominent and rather acute : within purple. ^ . . j. — S. 

 America. 



C Woodiana. Lea. Tr. Am. Ph. 5. t. 18./ 55. Sub-tri- 

 angular, ovate, thick, obtusely angular, anteriorly sub-equilateral, 

 convex, shining except on the anterior slope, blackish brown, with 

 transverse large wrinkles : beaks large, rounded : inside white, car- 



