156 
CONCHIFERA. 
Pecten . 
P. sulcatus. Sowerby, IY. 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 witli small scales; and the intercostal sulci longi¬ 
tudinally striated ; margins scolloped; ears nearly equal. 
The Pleistocene Marine Formation, Paisley, Ayrshire ; 
Mammiferous Crag, Southwold, the Red Crag, Sutton, and 
the Coral Crag, Ramshot. 
36*. Pecten sthiatus. —Tho Striated Pecten, pi. LXIY. 
fig. 18. 
P. striattes. Sowerby, IV. p. 130, pi. 394, figs. 2, 3, 4. 
P. limatus . G51dfuss, 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. 
Tho Red Crag, Sutton, and Coral Crag, Ramshot. 
37. Pecten vagans.* —Tho Wandering Pocten, pi. LXIY. 
fig. 20. 
P. vagans. Soworby, YI. 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 arc 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. —Tho Emperor Pecten, pi. LXII. 
fig 13. 
P. princeps. Sowerby, YI. 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 orbicularis. —The Orbicular Pecten,pi. LXIY. 
fig. 6. 
P. orbicularis. Sowerby, II. p. 193, pi. 186. 
Orbicular; greatly compressed; ono valve smooth, with 
wide-set, equidistant, elevated, sharp, concentric stria*; ears 
nearly equal, rather large, and broadest at the base; shell 
rather tender. 
The Upper Greensand, Devizes and Ilamsey, and the Lower 
Greensand, Maidstone and Pulborougli. 
40. Pecten abjectus. —The Abject Pecten, pi. LXY. fig. 9. 
P. abjectus. 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. 
Tho Great Oolito, or Gray Limestone, Mai ton and Whit- 
well, Yorkshire. 
41. Pecten anisotcs. —-pi. LXY. 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 stria), with distant lines of 
growth. 
Carboniferous Limestone, Yorkshire. 
42. Pecten arenosus. —The Sandy Pocten, pi. LXY. 
figs. 10, 11. 
P. arenosus. 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 
stria*. 
The Carboniferous Limestone, Closterdale, Bolland, and 
Derbyshire; and Kildare and Kulkeah, Ireland. 
43. Pecten cjngillatus. —The Banded Pecten, pi. LXIY. 
fig. 8. 
P. cingillatus. Phillips, Geo. York, I. pi. Y. 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 Pocten, 
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 demtssus— The Humble Pecten, pl.LXY.fig. 15. 
P. demissus. Phillips, Geo. York, I. pi. 6, fig. 5. 
Elongated, sides finely rounded ; ears equal and small. 
The Kelloways Rock, Scarborough ; tho Coral Crag, Mal- 
ton ; the Cornbrash, Gristhorpe, Yorkshire; and the Great 
Oolite, Clough ton. 
46. Pecten deornatus.— ^Unadorned Pecten, pi. LXY. 
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. LXY. 
figs. 20, 21. 
P. dissimilis. Phillips, Geo. York, IT. 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 fiat, nearly obsolete, concentric ribs. 
Carboniferous Limestone, Bolland. 
48. Pecten ellipticus. —The Elliptical Pecten, pi. LXY. 
fig. 19. 
P. ellipticus. Phillips, Geo. York, IT. 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. LXY. 
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. — Tho Interstriate Pecten, 
pi. LXY. fig. 28. 
P. interstitiales. Phillips, Geo. York, II. p. 212, 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 stri®. 
Tho Carboniferous Limestoue, Hawes and Bolland. 
