197 



M. Walch describes a similar fossil, Supp. PL v. c. p. 151, as a very 

 rare shell, which was found at Guntershofen, and which, he thinks, 

 might he very well placed among the tellenites. A similar fossil had been 

 previously found at Neustrelitz, in Mecklenhourg, in a grey lime-stone, 

 and described and figured in Magazin dc Berlin, 1. 1 v. This shell M. Walch 

 describes as having the point of the hinge elongated ; and striae, or raised, 

 elongated, and rather oblique ribs, of which, those which are nearest the 

 hinge unite and form an angle. The analogue of this shell, he observes, 

 has not yet been found. M. Martini observes, with respect to this shell, 

 that he has riever seen any recent or fossil shell resembling it, having 

 these converging striae, in the form of a bow, with cordiform interstices. 



LETTER XIV. 



PHOLAS FISTULANA TEREDO DICER AS ACARDO RA- 



. 



DIOLITES CHAM A SPONDYLUS PLICATULA GRYPH^A..... 



OSTREA. 



LAMARCK, in his Systeme des Animaux sans vertebres, had placed Pholas 

 at the end of the equivalved shells, and characterized them as having 

 accessory pieces ; and the genera Teredo and Fistulana he placed at the 

 head of the inequivalved shells, and distinguished them as having the 

 principal valve tubular. 



Since that period, in his Suite des Memoires sur les Fossiles des Environs 

 du Paris, under the article Fistulana , he says, that he was for a long 

 time perplexed, whilst endeavouring properly to characterize this sin- 

 gular kind of shell, because he considered, as all other naturalists had 



