PLATE LXXII. 
I, 2. Modiola Lineata* ( Lineated Modiola.) Elongated, ventricose, arcuated; beaks obtuse ; margins arched, parallel; surface, 
with fine striae, crossed by remote lines of growth. 
3. M. Bella. (Neat Modiola.) Ovate, convex; beaks obtuse; edges parallel; surface smooth, with fine, distant striae. 
4. Plagiostoma Elongatum. (Elongated Plagiostoma.) V. Plate LXVI., Fig. 4. 
5,6. M. Gibbosa. ( Gibbous Modiola.) Transversely elongated; reniform, gibbose; back broad, arcuated; posterior lobe well 
defined, inflated; surface smooth. 
7. M. Elegans. (Elegant Modiola.') Oblong, gibbose; convex; lower margin dentated, with transverse sulci; posterior side 
inflated, with a few, transverse furrows; beaks curved, with fine, undulating striae; interior often pearlaceous. 
8. M. Hillana. (Hill's Modiola.) Elongated ovate; posterior side narrow; posterior lobe obscure; front concave; back 
carinated; surface, with concentric striae. 
9. 10. M. Bipartita. ( Two-parted Modiola.) V. Plate LXXI., Figs. 22, 23. 
II, 12. M. Produeta. (Produced Modiola.) Elongated, inflated, arcuated; beaks obtuse; side under hinge-line produced; 
surface smooth; lines of growth slightly defined. 
13,14. M. Aspera. (Rough Modiola.) Ovate, transversely elongated; posterior side acute, gibbose; posterior lobe obscure, 
small, pointed ; surface, with many, transverse, rough striae. 
15,16. M. Subtruncata. (Sub-truncated Modiola.) Sub-quadrangular ; hinge-line lengthened, straight, oblique ; surface smooth. 
17. M. AldaraL (Aldam's Modiola.) Elongated; anterior side narrow; posterior side large, rounded; liinge-lino straight, 
lengthened; umbones small, obtuse; surface, with many, fine striae. 
18. M. Flexuosa. (Flexuous Modiola.) Elongated; anterior side narrow, short; beaks obtuse; base straight, with flexure 
below it; surface smooth, with remote, shallow lines of growth ; sides below beaks flexuous on edge. 
19. 20. M. Curtata. (Cut-off Modiola .) Oblong; beaks small, flat; anterior side short, rounded; posterior side large, with 
extremity truncated ; surface smooth, with some faint lines of growth. 
21, 22. M. Subcarinata. (Sub-carinated Modiola.) Transversely oblong ; front arcuated; anterior side keel-shaped ; posterior 
lobe convex, obtuse ; surface smooth, with well-defined lines of growth. 
23. M. Reversa. (Reverse Modiola.) Transversely elongated, compressed; anterior side narrow, short; umbones obtuse • 
posterior side expanded; surface, with narrow, regular, concentric ridges, reflected on surface. 
24, 25. M. Robertson!. (Robertson's Modiola.) Elongated, inflated; beaks sub-central, obtuse, rounded; hinge-line short; 
surface smooth, with remote, shallow lines of growth. 
26. M. Pulchra. ( Beautiful Modiola.) Transversely elongated; beaks rounded; anterior side rounded, short; posterior side 
expanded, truncated; surface smooth, shining, with a series of fine strife; lines of growth remote, distinct; basal line straight. 
27. M. Moorei. (Moore's Modiola.) Transverse, sub-cuneiform, inflated, smooth; base oblique; anterior side narrow; posterior 
side wide, sub-truncated; surface, with many, concentric lines of growth and fine intermediate striae. Length, £ in.; breadth greater. 
28. M. Minima. (Smallest Modiola .) Sub-triangularly ovate; sides rounded; posterior lobe small, distinct; front nearly 
straight; beaks small; surface smooth. 
29. M. Minuta. (Minute Modiola.) Transversely oblong-ovate, smooth; beaks small, produced, pointed; anterior side short, 
acute; hinge-line long, straight. Length, £ in.; breadth greater. 
30,31. M. Cuneata. ( Wedge-shaped Modiola.) Elongated, convex ; beaks obtuse; hinge-line straight; base concave ; seam of 
valves waved. 
32, 33. M. Reniformis. (Kidney-shaped Modiola.) Transversely oblong; sub-reniforra; anterior lobe expanded, pointed; 
posterior lobe small; surface smooth; centre of front indented. 
34. M. Inclusa. (Inclosed Mediola.) Ovate ; beaks produced; gently curved abovo and below ; surface smooth. 
35. M. ASqualis. (Equal Modiola.) Transversely oblong, convex, smooth ; anterior lobe ill-defined ; front parallel. 
36. M. Imbrieata. (Imbricated Modiola.) Oval, elongated; front concave; anterior lobe forming slightly elevated ridge ; beak 
angular ; surface, with imbricated ridges. 
37. M. Lsevis. (Smooth Modiola.) Sub-triangular, convex; posterior and lower margin straight; posterior side produced, 
united by a short curve; beaks small; surface smooth, with faint lines of growth. 
38. M. Undulata. (Waved Modiola.) Transversely elongated, oblique; beaks largo, obtuse; hinge-line curved, with wing¬ 
shaped expansion, with double flexure beneath; anterior side oblique from beaks ; base, with a curve towards centre. 
39. M. Squamifera. (Scaly Modiola.) Transversely elongated, narrow; beaks obtuse; hinge-line lengthened, straight, with 
abrupt flexure beneath; anterior side short; posterior side elongated; surface, with broad, laminated lines of growth. 
40. M. Pallida. (Pale Modiola.) Oblong, gibbose; inferior margin straight; posterior side inflated; beakB obtuse; surface 
smooth, glossy. 
41. M. Depressa. (Depressed Modiola.) Ovate, depressed; margin even, regularly curved; beaks rounded; surface smooth, 
shining, pearlaceous within. 
42. M. Lingualis. (Tongue-shaped Modiola.) Elongated, transversely tongue-shaped; anterior side narrow, short; hinge-line 
straight, lengthened ; beaks depressed; basal line curved; surface smooth, with delicate lines of growth. 
43. M. Elongata. (Elongated Modiola.) Elongated, arcuated, gibbose; margins parallel; sub-carinated; surface smooth, witli 
shallow, faint lines of growth. 
44,45. Lithophagus Antiquus. (Ancient Lithophagus.) Cylindrical; beaks blunt; surface smooth, with a few transverse 
striae towards umbones. 
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