PLATE XXI. 



Fig. 1. — Amusium yplanieostatum. A right valve. From Little Island, co. Cork. 

 In the Collection of Mr. J. Wright. (Page 124.) 



Fig. 2. — Amusium planicostatum. A left valve, the type of M'Coy's Pecten 

 planicostatus. Same locality. In the Griffith Collection, Museum of Science and 

 Art, Dublin. (Page 124.) 



Fig. 3. — Amusium planicostatum. A left valve. Same locality. Mr. J. 

 Wright's Collection. (Page 124.) 



Fig. 4. — Amusium tenue. The right valve. From East Kilbride. In the 

 Collection of Mr. J. Neilson. (Page 123.) 



Fig. 5. — Amusium tenue. A right valve, showing radiating ridges through the 

 shell. Same locality and Collection. (Page 123.) 



Fig. 6. — Amusium tenue. A left valve. From Northumberland. In the York 

 Museum. (Page 123.) 



Fig. 7. — Amusium concentricum. A right valve. From Croag, co. Limerick. 

 In the Collection of the Geological Survey of Ireland. (Page 122.) 



Fig. 8. — Amusium concentricum. A right valve. From Thorpe Cloud. My 

 Collection. (Page 122.) 



Fig. 9. — Amusium concentricum. A right valve. From St. Doulaghs, co. 

 Dublin. My Collection. (Page 122.) 



Fig. 10. — Amusium concentricum. A right valve. From Thorpe Cloud. My 

 Collection. (Page 122.) 



Fig. 11. — Amusium concentricum. A specimen showing very distinct and regular 

 concentric lines. From Little Island, co. Cork. Mr. J. Wright's Collection. 

 (Page 122.) 



Fig. 12. — Pseudamusium gihbosum. A left valve. From Castleton. My 

 Collection. (Page 106.) 



Fig. 13. — Pseudamusium anisotum. Phillips's type specimen. No locality given. 

 In the Gilbertson Collection, Natural History Museum, South Kensington. (Page 

 104.) 



Fig. 14. — Pseudamusium anisotum. The left valve of a medium-sized shell. 

 From Park Hill. My Collection. (Page 1 04.) 



Figs. 15, 16. — Pseudamusium anisotum. The left and right valves of a bivalve 

 example. From Hill Bolton, Yorkshire. My Collection. (Page 104.) 



Fig. 17. — Pseudamusium anisotum. The right valve. From Thorpe Cloud. 

 My Collection. (Page 104.) 



Fig. 18. — Pseudamusium anisotum. A large example of the left valve; the 

 anterior ear has been broken off. Same locality and Collection. (Page 104.) 



Fig. 19. — Pseudamusium anisotum. A right valve. Same locality and Collec- 

 tion. (Page 104.) 



Fig. 20. — Pseudamusium anisotum. A right valve, with remains of concentric 

 colour-bands. Same locality and Collection. (Page 104.) 



