158 PHOLAS. PIERCE-STONE. Class VI. 



and pholas is mentioned by Aristotle and 

 Athenaus; but I suspect it to be the dactylics 

 of Pliny. A species now called datyl, abound- 

 ing within the rocks of the Mediterranean, is 

 much admired as a food.* 



I have often taken them out of the cells they 

 had formed in hard clay, below high-water 

 mark, on many of our shores. They also per- 

 forate the hardest oak plank that accidentally 

 is lodged in the water. I have a piece filled 

 with them, which was found near Pensacola 

 in West Florida, and presented to me by that 

 ingenious naturalist the late John Ellis, Esq. 



I have also found them in masses of fossil 

 wood, in the shores of Abergeleu in Denbigh- 

 shire. The bottoms of the cells are round, and 

 appear as if nicely turned with some instru- 

 ment. 



* Pliny, lib. ix. c. 6l. Jrmstrongs Hist. Minorca, 173. 



