PECTEN. 



Plate X. 



Species 39. (Fig. a, Mus. Saiil, and Fig. b, 

 Mus. Cuming.) 



Pecten JacoBjEUS. Pect. testa suboblongo-ovatd, sub- 

 aquilaterali, inaquivalvi, costis qimtuordechu ad qitht- 

 decim radiatd ; valvd -sinistra concavo-planulatd, costis 

 plus minus elevatis, superne rotundatis, iuterdum mar- 

 ginem versus plamdatis et tenne liratis, rufo-fuscd, 

 purpureo-castaneo maculatd ; valvd dextrd alba, costis 

 acute quadratis et liratis, in testdjuniore interdum mi- 

 nute squamatis, interstitiis profniide excavatis ; auriculis 

 aqualibus. 



The St. James Pecten. Shell somewhat oblong-ovate, 

 nearly equilateral, inequivalve, rayed with fourteen to 

 tifteen ribs ; left valve concavely flattened, ribs more 

 or less raised, rounded at the upper part, sometimes 

 flattened and finely ridged towards the margin, red- 

 brown, spotted with purple-chestnut ; right valve 

 white, with the ribs sharply squared and ridged, in 

 the young shell sometimes minutely scaled, interstices 

 deeply excavated ; ears equal. 



Ostrea Jacobaa, Linnaeus, Syst. Nat. (12th edit.) p. 1144. 

 Pecten Jacobaus, Lamarck. 



Hab. Mediterranean. 



In the young shell represented at Fig. 39 a, the ribs 

 are remarkably raised, those of the right valve being 

 thickly finely squamate throughout. 



Species 40. (Fig. a, b, Mus. Cuming.) 



Pecten subbufus. Pect. testd nubrotundatd, tenui, com- 

 pressivscidd, subrcquilaierali, tequivalvi, costis ad viginti 

 angustis, liratis et squamatis, radiatd; purpureo-ru- 

 fescente, vel aurantid, vix maculatd ; auriculh inaqua- 

 libus. 



The reddish Pecten. Shell nearly rounded, thin, 

 rather compressed, nearly equilateral, equivalve, 

 rayed with about twenty narrow ribs, which are 

 ridged and squamate ; purple-red or orange, scarcely 

 spotted ; ears unequal. 



Tdrton, DithyraBrit. p. 210. pi. 17. f. 1. 



Pecten opercularis, var., Forbes and Hanley. 



Hab. Britain. 



There is little doubt of this being anything more than a 



variety of P. opercularis. 



December, 18.52. 



