Class VI. ARCA. ARK-SHELL. 217 



nated; teeth of the hinge about ten, quite 

 transverse. 



Found on the coast of CormvaU, and on the ' • 

 shores of Guernsey. 



Lin. Syst. 1143. No. \M. Moht. Test. Br. 136. 6. pilosa. 



Gm.Lin.33U. A. Glycymeris. Br. ZooL iv, orhcular. 



List. Conch, tah. 2^1. jig. 82. gS. 



Lin. Tr. viii. 94. t. 3./. 4. ' / 



A. with thick orbicular shells, marked with 

 concentric strice ; white zigzagged with ferrugi- 

 nous ; edges crenulated ; hinge in the middle, 

 and hinge teeth oblique. Diameter about two 

 inches. Tab.\\i.Jig.\. , 



Lin. Syst. 1141. No. 184. Lin. Tr. vlii. 95. 7. nucleus. 



Gm. Lin. 3314. Mont. Test. Br. 141. silvery. 



A. with unequally triangular shells; smooth, 

 pure white without, silvery within ; margin 

 finely crenated. Size of a pea. 



Gin. Lin. 3308. Mo7it. Test. Br. Sup. 55. t. 27. f. 7. 8. rostrata. 



* A. with a somewhat ovate convex shell trans- 

 versely striated; the hind part rounded, the 

 fore part produced into a bent lip. 



St. Abb's head. Frith of Forth. ' ■ 



