PLATE XXVIII. 



Fig. 1. — Edmondia union if or mis. The type of ~Phi\]ipss Isocardon unioniformis. 

 Preserved in the Gilbertson Collection of the Natural History Museum, South 

 Kensington. (Page 291.) 



Fig. 1 a. — Edmondia unioniformis. The same specimen viewed from above. 



Fig. 2. — Edmondia unioniformis. A perfectly-preserved specimen (a cast). 

 From Tomdeeby, Limerick. In the Collection of the Geological Survey of Ireland. 

 (Page 291.) 



Fig. 2 a. — The same specimen viewed from above. 



Fig. 3. — Edmondia unioniformis. A left testiferous valve. From the Redes- 

 dale Ironstone, Bellingham. My Collection. (Page 291.) 



Fig. 4. — Edmondia unioniformis. A right testiferous valve. From the Car- 

 boniferous Limestone of Castleton, Derbyshire. My Collection. (Page 291.) 



Fig. 5. — Edmondia unioniformis. The cast of both valves. Same locality. 

 My Collection. (Page 291.) 



Fig. 5 a. — Edmondia unioniformis. The same specimen, viewed from the front, 

 showing the absence of the lunule. 



Fig. 6. — Edmondia unioniformis. A beautiful example of the left valve. From 

 the Limestone of Rockfort Lodge, Bandoran. In the Collection of the Geological 

 Survey of Ireland. (Page 291.) 



Fig. 7. — Edmondia unioniformis. A testiferous left valve. From Castleton, 

 Derbyshire. My Collection. (Page 291.) 



Figs. 8, 9. — Edmondia rudis. Two very well-preserved specimens (casts) of 

 the interior. From the Lower Limestone shales of Beith. In the Collection of 

 Mr. J. Neilson. (Page 302.) 



Fig 10. — Edmondia rudis. A specimen from the same locality, viewed from 

 above, showing the grooves for the lamellar process of the hinge-plate. My 

 Collection. (Page 302.) 



Fig. 11. — Edmondia rudis. The cast of the interior of a medium-sized 

 example. Same locality. My Collection. (Page 302.) 



Figs. 12 — 14. — Edmondia rudis. Three examples, dwarfed in size. From the 

 Pennystone Ironstone Coal-measures, Coalbrookdale. My Collection. (Page 

 302.) 



