TAPES. 383 



Venerupis perforans. Lam. Anim. s. Vert. (ed. Desh.) vol. vi. p. 162. — Tukt. 



Dithyra Brit. p. 29, pi. 2, f. 15 to 18.— Flem. Brit. 



Anim. p. 451. — Brit. Marine Conch, p. 61. — Crouch, 



Introd. Conch, pi. 5, f. 5. — Hanl. Recent Shells, p. 54. 



— Philippi, Wiegm. Archiv. f. Natur 1845, p. 190, yA. 7, 



f. 15 to 18, 

 Vencriipis tiudeus. Lam. Anim. s. Vert. (ed. Desh.) vol. vi. p. 162. — Macgilliv. 



Edin. New Phil. Journ.( Jameson's) 1827, p. 370. — Deles. 



Rec. Coquilles, pi. 5, f. 1, — Hanl. Recent Shells, p. 54. 

 Venus palustr is, Mawe, Lin. Conchology, pi. 10, f. 3. 



Venerupis pullasira, Flem. Brit. Anim. p. 451. — Macgilliv. Moll. Aberd. p. 269. 

 Venerupis vulgaris, Sowerby, Concholog. Manual, f. 97. 

 Venus vulgaris, Broderip, Penny Cyclop, vol. xxvi. p. 211. 

 Pullasira vulgaris. Brown, lllust. Conch. G. B. p. 89, pi. 37, f. 7. 

 Pullasira perforans. Brown, lllust. Conch. G. B. p. 89, pi. 37, f- 10. 

 Venus plagia, (Var.) Jeffreys, Ann. Nat. His. vol. xix. p. 313. 



The V. pullasira was long regarded as at most a variety 

 of the preceding, to which alone of our British shells it 

 bears much resemblance. Its distinctness from decussata 

 was first pointed out by Mr. Wood, (the author of a 

 valuable work entitled, '' General Conchology,*" contain- 

 ing figures and descriptions of many rare species, which 

 are hardly to be met with elsewhere,) who founded his se- 

 parating characters chieHy from the structure of the hinge. 

 The more easily distinguishable differential features, are 

 stated by Colonel Montagu to consist of its smaller size, 

 the greater delicacy of its decussation, (which, moreover, is 

 never verrucose anteriorly, and which posteriorly has a 

 concentric and not a radiating arrangement,) the greater 

 regularity and approximation of its teeth, and the more 

 ample sinus of the pallial impression. To these we may 

 add, the greater shortness and usually lesser declination of 

 the front dorsal margin. The animal is also sufficiently 

 distinct. An examination of a long series of specimens, 

 which clearly connect the rock-dwelling joerforans, with 

 its type pullasira, and display the want of permanency in 

 the supposed specific characters of the former, compels us 

 to unite the two under one appellation. 



