116 



twenty radiating rather convex ribs, which are some- 

 what roughened by obsolete longitudinal and minute 

 transverse striae, and are narrower than their in- 

 terstices ; the color extremely variable, being yellow, 

 white, pink, &c., but the lower valve always white. 

 Variety.?. LINEATVS. Lam. 35. Da. Cost. t. 10. / 

 8. Mont. p. 47. Pen. 4.p. 222. OSTREA L. Lin. 

 T. 8. p. 99. Dor. Cat. p. 38. D. p. 266. The 

 rays marked each with a longitudinal red line. 2. 

 Very common. 



P. SUBRUFUS. Turt. B. p. 210. t. 11. f. 1. 

 OSTREA S. Don. 1. t. 12: Equivalve, suborbicular, 

 equilateral arid smooth, uniform rufous brown the 

 twenty radiating ribs rounded and smooth. Torbay. 

 A few transverse scaly marks towards the margin. 



P. SINUOSUS. Pen. 4. p. 222. t. 64. / 2.F. p: 

 384. Lam. 49. Turt. B. p. 210. t. 9. /. 5. 

 OSTREA S. Gmel. 3319, Lin. T. 8. p. 99. Dor. 

 Cat. p. 38. t. 10. /. 3,6. D. p. 262. Turt. D. p. 

 130. P. DISTORTUS. Da Cos. p. 148. t. 10. f. 3,6. 

 Mont. p. 148. P. Pusio. Don. l.t. 34. Sow. G. 

 List. t. 172. /. 9. Reeve, t. 114. /. 6. Suborbicu- 

 lar or longitudinally oval, inequivalve, variously dis- 

 torted, white, pink or brownish, irregularly marbled or 



