170 VENUS. 



verse tooth of the opposite valve. Adanson's description of 

 Le Tosar, from which Gmelin has constituted his Tellina 

 Senegalensis answers to this species. 



caliste. 25. Shell somewhat heart-shaped, with 

 acute transverse striae, becoming membrana- 

 ceous towards the margin; anterior depres- 

 sion short and the posterior obsolete. 



Venus Caliste. Gmelin, p. 3277. 



Venus, No. 6. Schroeter Einl. iii. p. 156. t. 8. f. 8 

 and 9. 



Inhabits the Red Sea. Schroeter. 



This shell is about the same size and figure as V. circinata ; 

 the colour is said to be generally dirty white, with the an- 

 terior end tinged with pale blue on the outside, and with 

 dark blue within. 



compressa. 26. Shell oval-heart-shaped, much com- 

 pressed, with transverse, remote, parallel 

 striae, and both the depressions linear; mar- 

 gin very entire. 



Venus compressa. Linnceus Mant. p. 546. Gmelin, p. 

 3282. 



Inhabits 



Linnaeus has not given any reference, or mentioned either the 



size or colour of this species, and it has not been ascertained 



by any subsequent author. 



exalbida. 27. Shell somewhat heart-shaped, flat- 

 tish, with transverse, elevated, slightly mem- 

 branaceous striae ; anterior depression lanceo- 

 late and wrinkled. 



Venus exalbida. Chemnitz, xi. p. 227. t. 202. f. 1977- 

 Inhabits the coasts of the Falkland Islands. Chemnitz. 

 Shell two inches and three-quarters long, and three inches 



broad ; white, without any coloured markings. Chemnitz 



says he received his specimen from London, under the name 



of V. cretacea. 



petulca. 28. Shell somewhat heart-shaped, slightly 

 grooved, and the margin crenulated ; cartil- 

 age cleft, sub-ovate, gaping ; nymphae acute. 



