PLATE XIV. 

 Fig. 1. — Ptcrinopecten Dumontianus. The left valve. In the Manchester 

 Museum, Owens College. (Page 65.) 



Fig. 2. — Pterinopecten Dumontianus. The right valve of the same shell. 

 (Page Go.) 



Fig. 3. — Aviculopecten Murchisoni. The type of M'Coy's Pecten Mnrchisoni. A 

 left valve. In the Griffith Collection, Museum of Science and Art, Dublin. (Page 

 99.) 



Fig. 4. — Aviculopecten Murchisoni. A left valve, showing the prolongation of 

 the ribs beyond the margin of the valve as spines. From the Carboniferous Lime- 

 stone of Derbyshire. Manchester Museum, Owens College. (Page 98.) 



Fig. 5. — Aviculopecten Murchisoni. Part of left valve, showing the rare 

 posterior wing. From Castleton. My Collection. (Page 98.) 



Fig. 6. — Aviculopecten Murchisoni. A small left valve, without the ears. From 

 Castleton. My Collection. (Page 98.) 



Fig. 7. — Aviculopecten Murchisoni. The right valve of the same shell. (Page 98.) 

 Fig. 8. — Aviculopecten Knockonniensis. A right valve. From above the Underset 

 Limestone, Farcote Gill, Westmoreland. My Collection. (Page 84.) 



Fig. 9. — Aviculopecten Knockonniensis. A left valve. From Salton, Scotland. 

 In the Collection of the Geological Survey of Scotland. (Page 84.) 



Fig. 10. — Aviculopecten Knockonniensis. A right valve. Same locality and 

 Collection. (Page 84.) 



Fig. 11. — Aviculopecten Knockonniensis. A left valve. From Derbyshire. In 

 the Woodwardian Museum, Cambridge. (Page 84.) 



Figs. 12, 13. — Aviculopecten Knockonniensis. Two young examples. Underset 

 Limestone, Farcote Gill. My Collection. (Page 84.) 



Fig. 14. — Aviculopecten inequalis. A specimen showing both valves. From 

 Boness. In the Collection of the Geological Survey of Scotland. (Page 99.) 



Fig. 15. — Aviculopecten inequalis. The small valve of the same specimen. 

 (Page 99.) 



Fig. 10. — Aviculopecten inter stitialis. A left valve, almost denuded of test. 

 From Castleton, Derbyshire. My Collection. (Page 95.) 



Fig. 17. — Aviculopecten inter stitialis. The right valve of the same specimen. 

 (Page 94) 



Fig. 18. — Aviculopecten inter stitialis. The left valve, showing the typical 

 ornament. Same locality and Collection. (Page 94.) 



Fig. 19. — Aviculopecten inter stitialis. Phillips's type specimen, and fragment of 

 a left valve. In the Gilbertson Collection, Natural History Museum, South Ken- 

 sington. (Page 94.) 



Figs. 20, 21. — Aviculopecten inter stitialis. Two left valves. From Wetton and 

 Castleton respectively. My Collection. (Page 94.) 



Fig. 22. — Aviculopecten Buthveni. M'Coy's type. Preserved in the Wood- 

 wardian Museum, Cambridge. (Page 97.) 



