GINGLYMACONCHA. PECTINID. 343 
This is the common Scallop of our markets, which is so 
much esteemed as a delicate article of food. 
Shells longer than high, sculptured with thick divaricating 
ribs ; the right valve rather flatter, with a deep notch, cilia- 
ted with minute spines ; the auricles equal. 
2. PECTEN OPERCULARIS. 
Shells roundish, with concentric, elevated, flat, undulated 
striz, or produced into tubercles; with eighteen or twenty 
rounded ribs longitudinally grooved. Length and height three 
inches and a half. 
Ostrea opercularis, Lister, Anim. Angl. t. v. f. 30; Conch. 
t. cix. f. 27, t. exci. f. 28; Petiv. Gaz. t. xciv. f. 1; Linn. 
Syst. Nat. 1147. no. 202; Born. Mus. 106; Gmel. Syst. 
Wat. 3a25; Da Cesta, Brit..Coneh: 144. t. 1x. f..1-5; 
Favanne, Conch. t. liv. f. L. 2; Chem. Conch. vii. t. lxvii. 
f. 646; Schroét. Einl. iii. 317. t. x. f. 3; Pult. Cat. Dor- 
set. 36. t. ix. f. 1-5; Brug. Encyel. Méth. t. cexni. f. 3 ; 
Dill. Dese. Cat. 265; Turété. Conch. Dict. 126. 
Ostrea dubia, Gmel. Syst. Nat. 3319. 
Ostrea elegans, Gael. Syst. Nat. 3319. 
Ostrea versicolor, Gmel. Syst. Nat. 3319. 
Pecten opercularis, Mont. Test. Brit. 145; Flem. Edinb. Ea- 
cycl. vii. 97; Lam. Hist. Nat. des Anim. sans Vert. vii. 
part.1. 172. 
Var. a. Pecten luteus, Da Costa, Brit. Conch. 144. t. ix. f. 5. 
Var. 6. Pecten subrufus, Lester, Anim. Angl. t. exe. f. 27; 
Penn. Brit. Zool. iv. 100. t. lx. f. 62. 
Yar. 6. Pecten subrufus, Donov. Brit. Shells, t. xii. 
Var. ¢. Pecten lineatus, Mont. Test. Brit. 147 ; Flem. Edinb. 
Eineyel. vii. 97; Lam. Hist. Nat. des dnim. sans Vert. vi. 
part. 1.172; Dill. Dese. Cat. 264. 
Ostrea radiata, Gmel. Syst. Nat. 3320. 
Var. a. Valves with a luteous epidermis. 
Var. 3. Valves with white purplish epidermis. 
Var. é. Valves with red epidermis. 
