156 



CONCHIFERA. 



Pecten . 



P. sulcatus. Sowerby, IV. p. 129, pi. 393, fig. 1. 



Orbicular, both valves convex, somewhat oblique, with from 

 eighteen to twenty obscurely tripartite ribs ; the whole sur- 

 face rough with small scales; and the intercostal sulci longi- 

 tudinally striated ; margins scolloped ; ears nearly equal. 



The Pleistocene Marine Formation, Paisley, Ayrshire ; 

 jMammiferous Crag, Southwold, the EeJ Crag, Sutton, and 

 the Coral Crag, Ramshot. 



30'. Pecten striatds. — The Striated Pecten, pi. LXIV. 

 fig. 18. 



P. striatus. Sowerby, IV. p. 130, pi. 39-i, figs. 2, 3, 4. 



P. limatus. Goldfuss, p. 59, pi. 94', fig. 6. 



Oval, both valves nearly equal and convex, with smooth, 

 irregular, scaly ridges ; margins entire ; ears rather large and 

 unequal, substance of the shell thick. 



The Red Crag, Sutton, and Coral Crag, Ramshot. 



37. Pecten vagans. — The Wandering Pecten, pi. LXIV. 

 fig. 20. 



P. Tar/ans. Sowerby, VI. p. 82, pi. 543, fig. 3, 4, 5. 



Ovate, a little longer than wide, convex ; with about eleven 

 large, convex ribs, provided with large, erect, concave scales, 

 wnich are close upon the right, but distant upon the left 

 valve ; ears nearly equal, crossed by scales. Sometimes ob- 

 scure furrows appear between the ribs. 



The Middle Oolite, Yorkshire and Wiltshire. 



38. Pecten princeps. — The Emperor Pecten, pi. LXII. 

 fig 13. 



P. princeps. Sowerby, VI. p. 80, pi. 542, fig. 2. 



A little ovate, compressed ; ears large, unequal, and squa- 

 mose ; surface with numerous divergent, narrow ribs ; thickly 

 covered with erect, equidistant concave scales ; margins cren- 

 ated by the projecting ribs. 



In the Coral Crag, Ramshot. 



39. Pecten oubicularis. — The Orbicular Pecten,pl. LXIV. 

 fig. 6. 



P. orbicularis. Sowerby, II. p. 193, pi. 186. 



Orbicular ; greatly compressed ; one valve smooth, with 

 wide-set, equidistant, elevated, sharp, concentric striae ; ears 

 nearly equal, rather large, and broadest at the base ; shell 

 rather tender. 



The Upper Greensand, Devizes and Hamsey, and the Lower 

 Greensand, Maidstone and Pulborough. 



4.0. Pecten abjectus. — The Abject Pecten, pi. LXV. fig. 9. 



P. aljectus. Phillips, Geo. York, I. pi. 9, fig. 37. 



Nearly orbicular, hinge-line oblique, ears small ; surface with 

 numerous longitudinal, divergent, narrow ribs ; crossed by 

 indistinct concentric stria; ; margin slightly crenulated. 



The Great Oolite, or Gray Limestone, Malton and Whit- 

 well, Yorkshire. 



41. Pecten anisotds. — pi. LXV. fig. 24. 



P. anisotus. Phillips, Geo. York, II. p. 212, pi. 6, fig. 22. 

 Oblong-oval, oblique ; ears unequal, one very large and the 



other very small, both longitudinally and transversely striated ; 

 surface with obscure divergent striaj, with distant lines of 

 growth. 



Carboniferous Limestone, Yorkshire. 



42. Pecten akenosus. — The Sandy Pecten, pi. LXV. 

 figs. 10, 11. 



P. arenosiis. Phillips, Geo. York, II. p. 212, pi. 6, fig. 20. 



Equal sided, body abruptly increasing ; ears small, unequal, 

 and square ; surface with numerous radiating stria>, alternately 

 larger and smaller; crossed by many minutely crenulated 

 strii-e. 



The Carboniferous Limestone, Closterdale, Bolland, and 

 Derbyshire ; and Kildare and Kulkeah, Ireland. 



43. Pecten cingillatus. — The Banded Pecten, pi. LXIV. 

 fig. 8. _ 



P. cingiUatns. Phillips, Geo. York, I. pi. V. fig. 11. 

 Elongated ; ears very small and nearly equal : surface cross- 

 ed by many wide set, equidistant, transverse ribs. 

 Cornbrash, Scarborough. 



44. Pecten concentricus. — The Concentric Pecten, 

 pi LXI.** fig. 18. 



P. concentricus. Woodward, Geo. Nor. pi. 5, figs. 27, 28. 

 Elongated, smooth, with irregularly placed, concentric ribs, 

 and depressed, divergent ribs ; ears unequal ; sides even. 

 Upper Chalk, Hartford Bridge, Norfolkshire. 



45. Pecten demissus. — The Humble Pecten, pl.LXV.fig. 15. 



P. demissus. Phillips, Geo. York, I. pi. 6, fig. 5. 



Elongated, sides finely rounded ; cars equal and small. 



The Kelloways Rock, Scarborough ; the Coral Crag, Mal- 

 ton ; the Cornbrash, Gristhorpe, Yorkshire ; and the Great 

 Oolite, Cloughton. 



46. Pecten deornatus. — Unadorned Pecten, pi. LXV. 

 fig. 25. 



P. deornatus. Phillips, Geo. York, I. p. 213, pi. 6, fig. 26. 

 Nearly orbicular and smooth, with small, nearly equal ears ; 

 surface with numerous equidistant, smooth, concentric furrows. 

 The Carboniferous Limestone, Yorkshire. 



47. Pecten dissimilis. — The Dissimilar Pecten, pi. LXV. 

 figs. 20, 21. 



P. dissimilis. Phillips, Geo. York, II. p. 212, pi. 6, fig. 17. 



Sub orbicular, slightly elongated ; the right or lower valves 

 with numerous longitudinal, slightly scaled ribs ; ears nearly 

 equal, slightly ribbed ; transversely and longitudinally striated; 

 upper valve concave, with flat, nearly obsolete, concentric ribs. 



Carboniferous Limestone, Bolland. 



48. Pecten ellipticds. — The Elliptical Pecten, pi. LXV. 

 fig. 19. 



P. ellipiicm. Phillips, Geo. York, II. p. 212, pi. 6, fig. 15. 

 Elliptical, compressed, smooth ; ears unequal, short ; sides 

 not much rounded. 



The Carboniferous Limestone, Bolland. 



49. Pecten fimbriatus. — The Fringed Pecten, pi. LXV. 

 fig. 22. 



P. fimbriatus. Phillips, Geo. York, II. p. 213, pi. 6, 

 fig. 28. 



Ovate ; compressed ; ears small and plain ; surface with 

 numerous imbricated, radiating ribs and furrows ; margin 

 slightly crenulated. 



The Carboniferous Limestone, Castleton, Derbyshire. 



50. Pecten interstitiales. — The Intei'striate Pecten, 

 pi. LXV. fig. 28. 



P. interstitiales. Phillips, Geo. York, II. p. 21 2, pi. 6, fig. 24. 



Oblong, oblique, with medium-sized, acute ears ; surface 

 with about sixteen longitudinal, sharp, radiating ribs ; the 

 intervening furrows with three finer ribs or striie. 



The Carboniferous Limestone, Hawes and Bolland. 



