693 



postice brunnea, omnino Hueis fuscis literata, seu varie picta seu 

 alba ; postice elongata, recta, truncata, oblique angulata,, post an- 

 gulum lirata, antice brevi, rotundata. 



More lengthened and much more finely striated in both direc- 

 tions than T. pullastra, with the hinge margin straight, and the 

 ventral margin a little turned upwards at the truncated posterior 

 extremity. The young is often quite smooth, and it is then V. 

 glandina of some authors. 



Mediterranean. 



51. Tapes pullastra (pi. cxlix. f. 85, 86), Wood (Venus), 

 General Conchology. Venus perforans, Mont. Test. Brit. p. 127. 

 pi. 3. f. 6. Venus Senegalensis, Dillwyn. Venerirupis perforans, 

 Lamarck. Venerirupis nucleus, Lam. Venus palustris, Mawe. 

 Pullastra vulgaris, Sowerby. Venus plagia, Jeffreys. 



T. testa rhomboidea, concentrice crcbre sulcata, radiatim minu- 

 tissime striata, pallide fulva, fulvo-rubescente pallide maculata, 

 nonnunquam intus postice purpurata, rugis posticis plus minusve 

 undulata ; latere antico brevi, vix angulato ; latere postico elon- 

 gato, subtruncato; margine dorsali postice recto, antice indis- 

 tincte lunulato, declivi ; margine ventrali vix arcuato. 



This species is subject to great variation, in consequence of the 

 different conditions in which it exists. When confined in holes of 

 rocks it becomes more oblong and irregular, with the rugosities 

 at the hinder extremity more marked; it is then the Venus 

 perforans of authors. When freely grown it is rhoinboidal, pretty 

 full, truncated and long at the hinder part, rounded and short at 

 the front ; the sculpture consists of concentric, slightly waved 

 strise, which are rugose and thick at the back, crossed by much 

 finer radiating stria;. 



Great Britain and northwards. 



52. Tapes decussata (pi. cl. f. 115, 115*), Linnceus 

 (Venus), Syst. Nat. p. 1135. Venus Florida, Poli, Test. Sicil. 

 pi. xxi. f. 16, 17. Venerirupis decussata, Flem. Pullastra de- 

 cussata, Brown. 



T. testa ovali, subrhomboidea, striis et rugis concentricis et 

 sulcis radiatis decussata, fulva, fusco et griseo varie picta ; latere 

 postico oblongo, rugis conspicuis, subtruncato ; latere antico 

 brevi, subrotundato. 



This well-known shell is of an oblong squarish form, rather 

 long, straight, and truncated behind, short in front, with the 



