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, Mtiller. 



Suborbicular, transparent, not ribbed ; with minutely squami- 

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

 cular sinus distinct. 



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



Pecten striatus, Mcljler, Zool. Danic.pl. GO, f. 3 to 5. — Alder, Cat. Northumb. 



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



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



b. c. 

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

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

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

 Pecten aculcatus, 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. 

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

 Brown, Illust. 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, PniLipn, 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. n. o o 



