PECTEN. 281 



even ninety fathoms, as we have found it in the Hebrides 

 and Zetlands (E. F.) It is most plentiful in from fifteen 

 to twenty-eight fathoms. The young ones seem to be 

 always free or moored by their byssus to corallines and 

 sea-weeds, and old examples almost always attached, glu- 

 ing their valves, by a process as yet not understood, to the 

 surfaces of stones, shells, and laminaria-roots, and assuming 

 consequently strange distortions of shape. 



It ranges throughout the European seas, and is found 

 fossil in the Upper Tertiaries of England. 



P. STRIATUS, Muller. 



Suborbicular, transparent, not ribbed ; with minutely squami- 

 ferous radiating costellar striae ; ears not very unequal, the auri- 

 cular sinus distinct. 



Plate LI. fig. 1 to 4, and (Animal) Plate S, fig. 2. 



Pecten striatus, Muller, Zool. Danic. pi. 60, f. 3 to 5. — Alder, Cat. Nortliumb. 



and Durh. Moll. p. 77. —Lovex, Index Moll. Scandinav. p. 31. 



Pallium vitreum (partly), Chemn. Concli. Cab. vol. vii. p. 335, pi. 67, f. 637, 



b. c. 

 Ostreafuci, Gmelin, Syst. Nat. p. 3327. — Dillw. Recent Shells, vol. i. p. 258* 

 — Index Testaceol. pi. 10, f. 27 ? (copied from Pecten reticulatus, 

 Chemn. Conch, cab. vol. xi. (p. 263) pi. 207, f. 2039, 2040.) 

 Pecten aculeatus, Jeffreys, Conch, and Malacolog. Magaz. vol. i. p. 40. — Brit. 

 Marine Conch, p. 249, f. 30. — Sowerby, Thesaur. Conch, 

 vol. i. p. 71, pi. 13, f. 47. 

 „ Landshurgi, Smith, Mem. Werner. Soc. vol. viii. p. 106, pi. 2, f. 2. — 

 Brown, lUust. Conch. G. B. p. 73, pi. 25, f. 8.— Hanl. 

 Recent Shells, vol. i. p. 282. 

 „ fuci, Thompson, Ann. Nat. Hist. vol. xviii. p. 385. 

 „ rimulosus, Philippi, Moll. Sicil. vol. ii. p. 60 (fossil) ? 

 „ spinosus, Johnston, Trans. Berwick Nat. Club. 



This beautiful and fragile bivalve is of such extreme 

 tenuity as to be often actually transparent. Its shape is 

 nearly circular, but rather broader than long ; its posterior 

 side is decidedly the shorter ; there is, however, no marked 



VOL. II. o o 



