114 



1. Arctica, Gray. 



2. Banksii, Leach. 



3. castanea, Say. 



4. cornpressa, Mont. 



5. crebricostata, Forbes. 



6. elliptica, Brown. 



Species. 



7. fusca, Poll. 



8. intermedia, Sow. 



9. lactea, Brod. 



10. oblonga, Sow. 



11. quadrans, Gould. 



12. semisulcata, Leach. 



13. subsequilatera, Sow. 



14. sulcata, D# Costa. 



15. triangularis, Mont. 



16. undata, Gould. 



Figure. 



Astarte sulcata. PI. 34. Pig. 186. Shell, showing the divergent 

 toothed hinge and dark fulvous epidermis. 



Genus 7. CYPRINA, Lamarck. 



Animal; with its mantle freely open, the edges being either plain 

 or serrated ; siphons projecting a little, icith the margins of 

 their orifices fringed ; foot large, linguiform. 



Shell ; obliquely cordate, convexly depressed, no lunule, covered 

 with a glossy, fibrous epidermis ; hinge of tico to three divergent 

 cardinal teeth and a remote lateral tooth in each valve. 



Of this genus only a single species is known, of large size, measuring 

 sometimes upwards of four inches in diameter. As its specific name de- 

 notes, the Cyprhia is purely a boreal moHusk, dwelling abundantly in the 

 North Atlantic seas, and ranging throughout the shores of Britain and 

 Ireland. Like Astarte the animal has no siphons, but the orifices project 

 more. The shell is of rather an opake white substance, covered with a very 

 decided glossy fibrous epidermis, of an olive or fulvous-brown colour. 



Figure. 



Cyprina Islandica. PI. 35. Pig. 190. 

 its remote lateral tooth. 



Shell, showing the hinge with 



Genus 8. GALATILEA, Bruguiere. 



Animal ; with the mantle freely open, margins simple ; siphons 

 elongated, separate ; foot large, oblong, compressed, slightly 

 angulated in front. 



