174 



CONCHIFERA. 



MODIOLA. 



Transverse, sub-cuneiform, inflated, smooth ; base oblique ; 

 anterior side narrow ; posterior side wide, and obliquely sub- 

 truncated ; surface witli many concentric lines of growth, and 

 very fine intermediate irregular stria;, which is only visible by 

 the aid of a lens. Length an eighth of an inch ; breadth 

 somewhat more. 



The Carboniferous Shale, Crimsworth Dean, Vale of Tod- 

 morden, Yorkshire. 



29. MoDioLA MiNUTA. — The Minute Modiola, pi. LXXII. 

 fig. 29. 



M. minuta. Brown, Manchester, Geo. Trans. I. p. 227, 

 pi. 7, fig. 75. 



Transversely oblong-ovate ; smooth ; beaks small, consider- 

 ably produced and pointed ; anterior side short, and a little 

 acute ; hinge-line rather long, and nearly straight ; length 

 one-eighth of an inch ; breadth somewhat more. 



The Carboniferous Shale, Low Moore, near Bradford. 



30. Modiola pulchra. — The Beautiful Modiola, pi. 

 LXXII. fig. 26. 



M. pulchra. Phillips, Geo. York, I. pi. 5, fig. 2G. 



Transversely elongated ; beaks rounded, aud placed near 

 the anterior side, which is rounded and short ; posterior side 

 expanded, and obliquely truncated ; surface smooth and shin- 

 ing, with a series of fine, radiating striue, emanating from the 

 beaks, and occupying the posterior half of the valves ; lines of 

 growth remote, distinctly marked ; basal line almost straight, 

 and nearly parallel with the superior line. 



The Kelloways Rock, Scarborough. 



31. Modiola squamifera. — The Scaly Modiola, pi. 

 LXXII. fig. 89. 



M. squamifera. Phillips, Geo. York, II. p. 209, pi. 5, f. 22. 



Transversely elongated, narrow ; beaks obtuse, hardly rising 

 above the surface ; hinge-line greatly lengthened, and quite 

 straight, ending in a point, beneath which lies an abrupt flex- 

 ure ; anterior side very short; posterior side much elongated ; 

 surface with distinct, broad, laminated lines of growth. 



The Carboniferous Limestone, Bolland. 



32. Modiola lingualis. — The Tongue-shaped Modiola, pi. 

 LXXII. fig. 42. 



M. linffuaJis. Phillips, Geo. York, II. p. 209, pi. 5, f. 21. 



Greatly elongated, transversely tongue-shaped ; anterior 

 side narrow, gradually widening towards the posterior side ; 

 hinge-line nearly straight and lengthened, from whence it 

 gently curves to the posterior side ; beaks depressed ; anterior 

 side extremely short ; basal line gently curved ; surface 

 smooth, with very delicate lines of growth. 



The Carboniferous Limestone, Castleton, Derbyshire. 



33. Modiola elongata. — The Elongated Modiola, pi. 

 LXXII. fig. 43. 



31. elongata. Phillips, Geo. York, II. p. 210, pi. 5, f. 24. 



Much elongated ; arcuated, rather gibbose, margins nearly 

 parallel; sub-carinated ; surface smooth, with very shallow, 

 nearly obsolete lines of growth. 



The Carboniferous Limestone, Bolland. 



34. Modiola inclusa. — The Inclosed Modiola, pi. 

 LXXII. figs. 34. 



J/, inclma. Phillips, Geo York I. pi. 3, fig. 20. 

 Ovate, beaks slightly produced ; gently curved both abeve 

 and below ; surface smooth. 



The Coral Rag, Malton, Wiltshire, and Oxfordshire. 



35. Modiola undulata. — The Waved Modiola, pi. 

 LXXII. fig. 38. 



M. cuneata (Var. ?) Phillips, Geo. York, pi. 5, fig. 28. 



Transversely elongated, oblique ; beaks large ; very obtuse, 

 hinge-line curved, and with a large wing-shaped expansion, 

 beneath which is a double flexure, anterior side obliquing from 

 the beaks ; base with a considerable curve towards the centre. 



The Kelloways Rock, South Cave, Scarborough. 



36. Modiola cuneata. — The Wedge-shaped Modiola, pi. 

 LXXII. figs. 30, 31. 



M. cuneata. Sowerbylll. p. 19, pi. 211, fig. 1. 



Elongated, convex, especially towards the beaks ; beaks 

 obtuse, hinge-line nearly straight, and protruding beyond the 

 surface ; anterior side not projecting so far as the beaks ; base 

 a little concave, seam of the valves waved. 



The Inferior Oolite, Somersetshire. 



37. Modiola latissima. — The Very Broad Modiola, pi. 

 LXXL, fig. 21. 



M. cuneata. Sowerby, III. p. 87, pi. 248, fig. 2. 



Transversely elongated ; length one-fourth its width ; a little 

 compressed ; anterior side slightly curved and produced ; 

 posterior side small, ill defined; beaks short and obtuse, 

 placed near the posterior side ; surface nearly smooth ; with 

 a few irregular, nearly obsolete lines of growth. 



38. Modiola rectus. — The Straight Modiola, pi. LXXII.* 

 fig. 7. 



Extremely lengthened transversely ; nearly straight ; beaks 

 hardly defined ; back nearly straight, base with a slight curve, 

 anterior side excessively short ; posterior side very much 

 lengthened ; back with a series of oblique rihs, which extend 

 about a third into the valves, and are then lost in a number of 

 retroverted wrinkles, which form an oblong triangular space 

 from the anterior side of the hinge-line to the opposite extre- 

 mity ; the other portion of the valves rather smooth, with 

 some shallow lines of growth. 



The Middle Oolite, Yorkshire. 



39. Modiola scalprum. — The Bill-shaped Modiola, pi. 

 LXXII." fig. 6. 



M. scalprum. Phillips, Geo. York, I. pi. 14, fig. 2. 



Extremely lengthened transversely, and much curved ; 

 beaks blunt and placed close to the anterior side ; hinge-line 

 much elongated and slightly bent from its termination ; the 

 shell is abruptly curved ; surface with numerous shallow lines 

 of growth. 



The Marlstone, Robin Hood's Bay, Yorkshire. 



40. Modiola amygdalina. — The Almond-shaped Modiola, 

 pi. LXL"-*figs. 11, 12. 



M. amygdalma. Phillips, Pal. Fos. p. 38, pi. 17, fig. 62. 



Elliptical, gibbous ; obliquely elongated ; narrowed ante- 

 riorly ; beaks close to the anterior side and incurved over the 

 lunule, which is excavated and small ; surface with fine con- 

 centric stria' and sharp lines. 



The Devonian Shale, Petherwin, Cornwall. 



41 . Modiola expansa. — The Expanded Modiola, pi. LXI.'- 

 fig. 13. 



M. expansa. Portlock, Geo. Rep. 425, pi. 33, fig. 6. 

 Elongated ; front produced considerably beyond the beaks ; 

 hinge-line straight, and equal in length to about half of the 



