50 CONCHYLI A— D/THFi?^. 15. 



hinge with a projecting round spoon-shaped tooth in each valve, 

 and a cavity close to it. 



This shell so very much resembles some specimens of the 

 Hiatella minuta, that without an examination of the hinge it might 

 be easily overlooked for it. That Linne knew them to be dis- 

 tinct is evident, from his having placed them in two different 

 genera, on account of the differences in the hinge. 



15. LISTEUA- TURTON. 



Testa transversa, ovata, wquivalvis, lateribus subhiantibus, Cardo 



dente cochleariformi cum denticulis adjectis : lateralibus nullis. 



Ligamentum externum. 

 Shell transverse, oval, equivalve, a little open at the sides. Hinge 



with a spoon^shaped tooth and additional denticles : lateral teeth 



none. Ligament external. 



This family differs from the Anatina, in having a small tooth or 

 two in addition to the spoon-shaped ones : and from the genus 

 Amphidesma in wanting the lateral teeth. 



It is named from Dr. Martin Lister, the Coryphaeus of all syste- 

 matic conchology. 



