PLATE XXXIV. 



Tribe, the term and cliaracter of Terebratula not being recognised 

 by that author as generically distinct from the Anomia. Our reasons 

 for this deviation shall be explained as briefly as it is possible : from 

 the nature of those remarks, and the extent of enquiry with which it 

 is connected, this cannot however be comprised within very slender 

 limits. 



In the Linnaean arrangement, the Anomia form a very compre- 

 hensive genus, and since in particular the fossil species are included 

 it should certainly have been divided into several distinct sections or 

 families in order to embrace the different tribes of those shells, which 

 according to the character Linnaeus has given of the genus must 

 necessarily be referred to it. It is impossible without some modifica- 

 tion of this kind to reconcile Anomia Ephippium and Cepa, with 

 A?i07nij Caput Serpentinus or Terebratula, or either of them with 

 A. Placenta ; and there are besides these some other families which 

 do not well accord, and which might perhaps be separated into 

 distinct genera with great advantage, the fossil kinds especially, which 

 are very numerous and much diversified in structure. It cannot be 

 very material whether they be so divided into genera or be placed in 

 different families under the general appellation of Anomiae : they are 

 obviously very dissimilar and should be kept apart, and we have 

 examples of both these modes of classing the Anomiae among the 

 early Naturalists. 



A late french writer, M. Bosc, speaking of this tribe of shells, 

 observes, that Linnaeus having confounded the Terehratules with the 

 Anomies, Brugiere first established their differences, and Lamarck 

 had fixed their characters. This observation is not sufficiently 

 explicit, and may possibly imply more than the author of it has 



