PLATE XIV. 



Fig. 1. — Parallelodon obtusus. A large example possessing both valves. In the Gilbertsou Collection, Natural 

 History Museum, South Kensington. (Page 167.) 



Fig. 2. — Parallelodon obtusus. A specimen showing part of the hinge-plate. Same Collection. (Page 167.) 



Fig. 3. — Parallelodon obtusus. An almost perfect specimen, showing the ligaineutal area. (Page 167.) 



Fig. 4. — Nueula gibbosa. The type of Phillips's N. tumida. From Northumberland. Same Collection. (Page 178.) 



Fig. 5. — Nueula gibbosa. A full-grown perfect example. From the lledesdale Ironstone, Northumberland. My 

 Collection. Fig. 5 a. — The same shell viewed from above. (Page 178.) 



Fig. 6. — Nueula gibbosa. A cast, showing the scars of the anterior and posterior adductor muscles. Same locality 

 and Collection. Fig. 6 a. — The same shell viewed from above, showing impression of the hinge-line. (Page 178.) 



Fig. 7. — Nueula gibbosa. A specimen showing the left valve. Same locality and Collection. (Page 178.) 



Fig. 8. — Nueula gibbosa. A left valve, showing the hinse-plate and interior of the valve. From Clonbeith, Kil- 

 winning. Collection of Mr. W. Smith, Kilwinning. (Page 178.) 



Fig. 9. — Nueula gibbosa. A left valve. From the Kedesdale Ironstone. My Collection. (Page 178.) 



Figs. 10, 11. — Nueula gibbosa. Two specimens from the shale below the Linn Limestone, Linn Spout, Dairy, to 

 show the maximum size for this locality. My Collection. (Page 178.) 



Fig. 12. — Nueula gibbosa. A perfect example from the shale below the third millstone grit, Congleton Edge. My 

 Collection. (Page 178.) 



Fig. 13. — Nueula gibbosa. From the roof of the Gin-mine Coal, North Staffordshire coal-field. Collection of Mr. J. 

 Ward, of Longton. (Page 178.) 



Fig. 14. — Nueula gibbosa. The interior of a left valve. From Den, Dairy. Collection of Mr. J. Smith. (Page 178.) 



Fig. 15. — Nueula gibbosa. The hinge-plate of a right valve, showing cartilage cavity. From Carboniferous Limestone 

 series, East Barns, near Edinburgh. Fig. 15 a. — The same shell enlarged. My Collection. (Page 178.) 



Figs. 16, 16 a. — Nueula ventricosa, Hall. Two views from a specimen from Oakwood Upper Coal-measures, Vermillion 

 CO., Illinois, to show the difference of this species from N. gibbosa. (Page 186.) 



Fig. 17. — Nueula luciniformis. A fine full-grown example from the neighbourhood of Glasgow. In the Col- 

 lection of the Woodwardian Museum, Cambridge. (Page 186.) 



Fig. 17 a. — Nueula luciniformis. The same specimen viewed from above. (Page 186.) 



Fig. 18. — Nueula luciniformis. The type specimen figured by Phillips. In the Gilbertson Collection, Natural History 

 Museum, South Kensington. Fig. 18 a. — The same shell showing right valve. Fig b. — Viewed from above. (Page 186.) 



Fig. 19. — Nueula luciniformis. A compressed specimen from Den, Dairy. In the Collection of Mr. J. Smith. 

 (Page 186.) 



Figs. 20, 21. — Nueula luciniformis. Two examples from Bishopriggs, Middle Limestone series. In the Collection 

 of Mr. J. Neilson. Fig. 22.— Showing cast of interior. (Page 186.) 



Fig. 23. — Nueula oblonga. The type figured by M'Coy. From the Griffith Collection, Museum of Science and Art, 

 Dublin. Figs. 24 — 27.— A series from the Upper Limestone of Orchard. Collection of Mr. J. Neilson. (Page 188.) 



Fig. 28. — Nueula undulata. The type specimen figured by Phillips. In the Gilbertson Collection, Natural History 

 Museum, South Kensington. Fig. 28 a. — The same specimen viewed from above. (Page 181.) 



Fig. 29. — Nueula undulata. The left valve of an almost perfect specimen from the neighbourhood of Glasgow. In 

 the Collection of the Woodwardian Museum, Cambridge. (Page 181.) 



Fig. 30. — Nueula undulata. A left valve from the Redesdale Limestone. My Collection. (Page 181.) 



Fig. 31. — Nueula undulata. A right valve. Same locality and Collection. (Page 181.) 



Figs. 32, 33. — Nueula xqualis. Two perfect examples from the shales below the third millstone grit, Congleton Edge. 

 My Collection. (Page 189.) 



Fig. 34. — Nueula xqualis. A cast showing muscles-scars and impression of the hinge. From the Pennystone Iron- 

 stone, Coalbrookdale, the locality whence the type was obtained. In the Collection of the Natural History Museum, 

 South Kensington. (Page 189.) 



Fig. 34 a. — Nueula xqualis. An enlarged view of the above. (Page 189.) 



Fig. 35. — Nueula xqualis. A specimen viewed from above to show the impression of the hinge-plate, with an enlarged 

 view, 35 a. Same locality. My Collection. (Page 189.) 



Fig. 36. — Nueula palmx. The type specimen figured by Sowerby. Said to come from Derby. (Page 185.) 



Fig. 36 a. — Nueula palmx. The type specimen viewed from above, and showing the impression of the hinge-teeth 

 and cartilage socket. (Page 185.) 



Fig. 37. — Nueula Scotica. A left valve, from Wilkieston, Fife, showing the hinge-plate. My Collection. (Page 191.) 



Fig. 37 a. — Nueula Scotica. Enlarged view. 



Fig. 38. — Nueula Scotica. The right valve, natural size. Wilkieston, Fife. (Page 191.) 



Fig. 39. — Nueula Scotica. A perfect example, full size, from the Lower Limestone series of Craigenglen. In the 

 Collection of Mr. J. Smith. Fig. 39 a. — An enlarged view. Fig. 39 b. — The same viewed from above. Fig. 39 c. — An 

 enlarged view of hinge-line and umbones. (Page 191.) 



Fig. 40. — Nueula undulata. A specimen showing the cast of the hinge of the roof of the Gin-mine Coal, North 

 Staffordshire. In the Collection of Mr. J. Ward. (Page 181.) 



