178 MYTILIDiE. 



solved in the sherbet of the nabobs ! However, at present 

 it is a mystery ; and, notwithstanding the pains taken and 

 the expense incurred by some liberal gentlemen in endea- 

 vouring to find out the secret, it is as great a mystery as 

 ever. The huts which have been erected for the con- 

 venience of boiling the fish, are on the extremity of the 

 marsh, about a mile north of the town of Conway. The 

 pearls are seldom found here much larger than the enclosed 

 specimens, though about twelve miles up the river, they 

 have been found occasionally as large as a moderate-sized 

 pea, and have been sold for a guinea the couple, but they 

 are very rarely met with. When I say that the price 

 varies from Is. 6d. to 4s. I do not mean to say that they 

 are valued according to their size, for the large and small 

 pearls are all sold together ; but some years ago they were 

 as high as 4s., now they are only 2s. per ounce." 



There is no occasion to enumerate localities for so com- 

 mon a shell as the Mytilus edulis, universally distributed 

 around our coasts, and plentiful in favourable localities near 

 the edge of low water, and in a fathom or two beyond. 

 The variety pellucidus ranges deeper. 



The species ranges all round the coasts of the North 

 Atlantic, on both its eastern and western sides, and into 

 the Mediterranean. It is found fossil in the red and mam- 

 maliferous crags, and everywhere in pleistocene deposits. 



SPURIOUS. 

 M. bidens, Linnaeus. 



Lister, Hist. Conch, pi. 366, f. 206. 

 Mytilus lidens, Linnaeus (not Born nor Dilmvyn), Syst. Nat. ed. 12, p. 115. 

 — Deshayes, Lam. Anim. s. Vert. (ed. Desh.) vol. vii. p. 39. 

 „ striahdus, Schroter, Einleit. Conchylien, vol. iii. p. 449, pi. 9, f. 16. — 

 Turton, Magaz. Nat. Hist. vol. vii. p. 350. — Brit. Marine 

 Conch, p. 110. — Index Testaceolog. pi. 12, f. 19. 



