52 CLASS I. TROPIOPODA. ORDER I. BIMUSCULOSA. 



ANATINA, Lamarck. 



Testa transversa, inrequilateralis, plerumque inaequivalvis, utroque latere 

 hians ; plerumque processu parvo, cochleariformi, ligamentifero, in 

 utraque valva ; appendice testacea curva, parva, interdum minima, 

 ante processus, ligamento connexa. 



From this genus, as established by Lamarck, three others have been 

 created, Periploma, Osteodesma and Thracia, the last of which we have 

 considered it necessary to retain. The true Anatina resembles Mya in its 

 habit of living buried in the sand ; but the shell differs in having the 

 spoon-shaped ligamentiferous process in both valves, approaching in this 

 particular to the shell of Lutraria, a genus of Mactracea. Its chief pecu- 

 liarity, however, is in the appearance of a small, curved, testaceous 

 appendage, situated before the spoon-shaped processes, and connected 

 with the ligament, serving to strengthen it. 



Examples. 



PI. XXXIV. Fig. 1. 



Anatina truncata, Lamarck, Anini. sans vert., new edit., vol. vi. p. 77. 

 Enc. Meth., vol. ii. p. 39. 



PI. XXXIV. Fig. 2. 



Anatina Norvegica, Sowerby, Genera of Shells, No. 33. 

 Amphidesma corbuloides, Lamarck. 

 Osteodesma corbuloides, Deshayes. 

 Mya Norvegica, Chemnitz. 



