114 



MOLLUSCA. 



Spirifer. 



Found on the Devonian Shale, at Hope, near Torquay, and 

 in South Devon. 



71. Spirifer obliteratus. — The Obliterated Spirifer, pi. 

 LIL* fig. 29. 



Spirifera ohliterata. Phillips, Pal. Fos. p. 77, pi. 31, fig. 



135. 



Convex, semicircular, its width twice its length ; cardinal area 

 with acute terminations; surface with slightly elevated radia- 

 tions, crossed by remote, well marked lines of growth ; mesial 

 furrow shallow, situate between two convex, but obtuse, nearly 

 central radiations. 



Allied to S. speciosus, fig. 24, 25. 



Found in the Mountain Limestone, in North Devon and 

 Brushford. 



72. Spirifer inornatus The Unadorned Spirifer, pi. 



LII.* fig. 37. 



Spirifera inornata. Sowerby, Geo. Trans. V. 2nd series, pi. 



53, fig. 9. 



Much elongated transversely, fusiform, compressed, and 

 smooth ; sides with obscure radiations ; base even ; beaks ob- 

 scure. 



Found at llfracombe, in the Devonian Shale. 



73. Spirifer extensus. — The Extended Spirifer, pi. LIL* 

 fig. 38. 



Spirifera extensa. Sowerby, Geo. Trans. V. 2nd series, pi. 



54, fig. U. 



Convex, greatly elongated transversely, and fusiform ; with 

 numerous radii, about seven in the middle of the upper valve 

 being more prominent than the others, and its beak small. 



Found in the Devonian Shale at Petherwood, Staunton, and 

 Barnstaple Bridge. 



74. Spirifer costatus. — The Ribbed Spirifer, pi. LIL* 

 fig. 35, 36. 



Spirifer costata. Sowerby, Geo. Trans. V. 2nd series, pi. 



55, fig. 5, 6, 7. 



Convex, fusiform, much elongated transversely ; surface with 

 two approximate, central, elevated ribs, and about five or six 

 rounded thick ones on each side of these ; lower valve with 

 abroad, deep sulcus, bounded by two strong ribs; hinge 

 area broad, with parallel edges. Length hardly a sixth of its 

 width. 



Found in soft Slaty Stone at Fowey, and in hard Blue Slate 

 at Tintagel and Looe. 



75. Spirifer ptychodes. — The Tooth-folded Spirifer, pi. 

 LIL* fig. 32, 33. 



Spirifer ptychoiles. Sowerby, Sil. Syst. p. 603, pi. 3, fig. 13. 



A little elongated, smooth, with fine, rounded, longitudinal 

 folds; beak of larger valve produced, and curved. Length and 

 width three lines and a half. 



Found in the Old Red Sandstone at Felinder, and also in the 

 Upper Ludlow Rocks. 



76. Spirifer Pisum — The Pea Spirifer, pi. LIL* fig. 

 30,31. 



Spirifera Pisum. Sowerby, Sil. Syst. p. 630, pi. 1 3, fig. 9. 



Convex, lenticular, smooth, indistinctly hexagonal; base even 

 truncated; beaks small, of equal length; cardinal area small, and 

 triangular. Length and width three lines. 



Found in the Wenlock Shale at Hay Head. 



77. Spirifer affinis The Allied Spirifer, pi. LIL* fig. 



34. 



Spirifera affinis. Sowerby, Geo. Trans. V. 2nd series, pi. 

 57, fig. 11. 



Lenticular, with numerous, longitudinal, rounded ribs, branch- 

 ed and crossed by thin laminae ; cardinal area flat, triangular, 

 shorter than the breadth of the shell ; beak of the lower valve 

 produced. 



Found in the Devonian Shale at Plymouth. 



78. Spirifer subconicus The Subconic Spirifer, pi. 



LIL* fig. 59. 



Spirifera subconica. Sowerby, Geo. Trans. V. 2nd series, 

 pi. 57, fig. 10. Phillips, Pal. Fos. p. 72, pi. 29, fig. 126. Am- 

 mites subconicus, Martin, Pet. Derb. pi. 45, fig. 6. 



Larger valve subconic, with a central, longitudinal sulcus, and 

 several strong, rounded, divergent ribs, crossed by a few distant 

 lines of growth ; cardinal area large, triangular, and flat. 



Found in the Carboniferous Limestone of Derbyshire, and 

 the Devonian Shale at Plymouth. 



79. Spirifer interlineatus The Interlined Spirifer, 



pi. LIL* fig. 41,42. 



Spirifer interlineatus. Sowerby, Sil. Syst. p. 614, pi. 6, 

 fig. 6. 



Convex, transversely ovate, with large, rounded ribs, five on 

 each side of a large, prominent, central one, and fine, close-set, 

 longitudinal striaj; beak of larger valve produced, and so greatly 

 incurved as to meet the beak of the smaller valve. Length five 

 lines and a half; breadth six lines and a half. 



Found in the Amestry and Wenlock Limestones. 



80. Spirifer trapezoidalis The Trapezoidal Spirifer, 



pi. LIL* fig. 43, 44. 



Spirifer trapezoidalis. Sowerby, Sil. Syst. pi 610, pi. 5, fig. 

 14. Cyrtia trapezoidalis. Von Buch, pi. 1, fig. 15. 



Nearly semicircular ; larger valve with a wide, deep, mesial 

 sulcus, and a corresponding elevated ridge in the other, with 

 fine, radiating striae ; hinge fine somewhat shorter than the 

 diameter of the shell ; area large, curved, with a narrow 

 foramen. 



Found in the Upper Ludlow Rock at Usk, Craig-y-garcyd, 

 and Iron Bridge, Coalbrook Dale. 



81. Spirifer grand^vus The Aged Spirifer, pi. LIL* 



fig. 45, 46. 



Spirifera grandceva. Phillips, Pal. Fos. p. 76, pi. 30, fig. 

 131. 



Semielliptical ; hinge line nearly straight, slightly projecting, 

 with somewhat square terminations ; lesser valve with a large, 

 elevated, rounded, mesial ridge, with distinct furrows on either 

 side, and about ten radiations on both sides. 



Found in the Devonian Shale at Petherwin, Cornwall. 



82. Spirifer crispus. — The Curled Spirifer, pi. LIL* 



fig. 47. 



Spirifer crispus? Sowerby, Sil. Syst. p. 624, pi. 12, fig. 8. 

 Dellhyris crispa, Dalm. 1. c. p. 122, pi. 3, tig. 6. 



Gibbose, transversely elongated ; with from five to seven 

 elevated plaits, crossed by strong laminae; hinge line with obtuse 

 ends; beaks remote. Length three lines and a half ; breadth 

 five lines and a half: sometines larger. 



Found in the Wenlock Limestone at Dudley and Walsall. 



