BIVALVE SHELLS. 201 



Cyprina islandica, Flem. Brit. Anim. p. 443. uo. 510. 

 Cyprina vulgaris, Sow. Gen. of Shells, f. 1,2. 



Fossilis. 



Nyst, Coq. Foss. Belg. p. 147. no. 101. pi. 9. f. 1. 

 Venus ffiqualis, Sow. Min. Conch, pi. 21. 

 Cvprina sequalis, Phil. Enum. Moll. Sicil. i. 39. 



Agass. Coq. Tert. p. 52. no. 2. pi. 13. f. 5. 

 Cyprina maxima, Wood, Cat. Foss. Shells from the Craq, Ann. 



Nat. Hist. vi. 24.9. 

 Cyprina angulata, Nyst, Rech. sur les Foss. Ano. p. 9. no. 34. 

 Cyprina Islandicoides, Nyst, loc. cit. p. 9. no. 33. 

 Cyprina islandica, Hisinger, Leth. Suec. Suppl. 2. p. 9. 



Phil. Enum. Moll. Sicil. ii. 31. 



Russell, Essex Journ. i. 37. 



De Kay, Zool. of New York, v. 215. 

 Cyprina vulgaris, Morris, Cat. Brit. Foss. p. 86. 



Hub. Oceanus Eiu-opaeus. 



Fam. 3. Glauconomidse. 



Animal oblongum, transversum ; pallium antice inferneque 

 apertum, postice clausum et tracheis binis basi conniventibus, 

 prselongis, lateraliter compressis terminatum ; pes minimus, coni- 

 pressus, oblougus, linguiformis ; ap])endices labiales latse, trian- 

 gulares, oblongffi, membranaceae ; branchiae elongata;, oblonga", 

 postice conjunctse. — Gray, Spic, Zool. 1826. 



Testa oblongo-ovalis, tenuis, ventricosa, aequivalvis, inaequi- 

 lateralis, antice rotundata, ]X)stice subacuminata, epidermide 

 viridi, tenui, cornea induta ; cardo augustus ; dentibus in utra- 

 que valva tribus, posticis majoribus, valvse dextrte medio sinistrae 

 postico bitidis ; impressiones musculares duse, antica oblonga. 

 marginali, postica subquadrata ; impressio pallii siuu angustis- 

 simo, profundo terminata; ligamentum externum, oblongum. 



GlauconomidBe, Gray, Ann. Sf Mag. Nat. Hist. 1853. 



Solenicurtes, pt.. Swains. Malac. 366 (1840). 



Solenacea, pt., Reeve, Conch. Syst. i. 48. 



Cyclades, pt., Potiez Sf Mich. Gall, de Douai, ii. 193 (1844). 



Solen, sp., Linn. 



Solenidaj, pt., Hanley, III. Cat. i. 11 (1844). 



This family differs from Veneridce in the form and disposition 

 of the cardinal teeth, the union of the mantle lobes, in the fresh- 

 water habitation, and in being covered with a hard green peri- 

 ostraca, which from its external appearance seems evidently to 



