274 TRIBE VECTINIDKS. 



internally striated, toothed at the margin, gaping on each side ; 

 ears equal and obtuse ; tawny, the margins purplish, with radiating 

 and concentric red bands; lower valve much lighter. 1-fa. . 1-i. 

 China. 



P. Pleuronectes. Lam. 7.—Soiv. Th. /. 127, 128, 135, 136. 

 —El. t. 60./ 5.— Ostrea P. Lin. 1145.— D. p. 250.— W. t. 

 10./. Q.—Gualt. t. 73. f. B.— Knorr. 1. t. 20./. 3, 4.— Ch.f. 

 595. — E. t. 208. /. 3. Orbicular suboval, smooth, compressed, gap- 

 ing on each side ; ears equal, obtuse ; internally, with twelve pairs 

 of slightly raised linear ribs, the insterstices substriated ; upper 

 valve pale greyish fawn, dark mahogany brown or purplish 

 pink, lighter near the umbo and radiated with bands of a darker 

 colour, each band defined by a sharp line on either side : lower 

 valve white. 3^. . 3\. China. 



P. Japonicus. Lam. 9. — Sow. Th. /. 109,0. — Ostrea J. Gmel. 

 3317.— Z). p. 250.— Ch. f. 596.— E. t. 208./. 4>.— W. t. 10. 

 /. 7. Orbicular, smooth, rather compressed, gaping considerably 

 on each side ; ears equal, obtuse, small ; internally with twenty- 

 two pair of ribs ; upper valve dull red with concentric lines and 

 bands of a darker tint, with faint light rays ; right valve white. 

 5±..5. China and Japan. 



P. Laurentii. Lam. G. — Sow. Th. / 137,8. — Ostrea L. 

 Gmel. 3317.— Ch.f. 593,4.— E. t. 208. /. l.— W. t. 10. /.8.— 

 O. Ziczac. Var. D. p. 249. Suborbicular, with a rounded angle 

 at each side, smooth ; the ears broad, rectangular, with undulated 

 margins ; upper valve rather flat, elevated at the sides, reddish 

 brown, faintly radiated with darker brown and speckled with 

 white, about forty-seven internal ribs ; lower valve radiated with 

 pale brown on a pale fawn ground, ventricose, rather compressed 

 at the sides, white at the umbones, with about forty-one internal 

 ribs. 3\. . 3f . China. 



P. Magellanicus. Lam. 10. — Sow, Th. f. \22.—Am. Mar. Con. 

 tl,/. 1.— Ostrea M. Gmel. 3317.— D. p. 250.— Ch.f. 597.— E. 

 t.208.f. 5.- — IV. t. 10./ 9. Orbicular, rather flat, gaping on each 

 side, radiated with numerous rough minute striae ; ears striated, 

 broad, rectangular ; the brown upper valve more ventricose than the 

 nearly white lower one. 3-±.. 3^. Massachusseis. 



P. Exoticus. Chem. f. 2037,8. — Desk ed. Lam. 7. p. 154. — 

 Ostrea E. D. p. 259.— W. t 10. /. 28.— P. Pseudamusium. 

 Sow, Th.f. 211, 2, fy 243. — Pseudamusium Lceve Klein, t. 9./ 31. 

 {a copy from List. t. 173.) Orbicular, compressed, smooth, or 

 most minutely striated ; ears flat, equal ; ash or pale fawn with 

 large brown spots. 1 T ^. . . 1-^-. Gambia, Africa. 



P. GRiENLANDicus. Sow, Th.f. 40. Equivalve, orbicular, rather 



