SUPPLEMENT, PLATE XVL 



Fig. 



1. &tro'phoinena Waltoni, Dav. Upper Llandovery, Ciiddyston Glen. Coll. of 



Mrs. R. Gray. (P. 195.) 



2^-5. „ arenacea, Salter. 2. Middle Llandovery, Woodland Point, 



Girvan. 3, 3«, 4, 5. Upper Llandovery, Cam- 

 regan Wood, Girvan. Coll. of Mrs. R. Gray. 

 (P. 197.) 



6, 7. „ Callawayiana, Dav. Caradoc, Marsh Brook, Gretton. Coll. of 



Dr. C. Callaway. (P. 193.) 



8, 8 a, b. „ Sltallockiensis, Dav. Middle Caradoc, Shallock Mill, Girvan. Coll. 



of Mrs. R. Gray. (P. 192.) 



9 — 12. „ ? bipartifa, Salter. Middle Caradoc or Chatvvall sandstone, south 



end of Ragleigh Hill, Vetnich Station, and 

 Caradoc, Ty-isaaf, Llansantffraid. Collections of 

 Messrs. C. Callaway and Croft. (P. 193.) 



13. Orthis reversa, Salter. Upper Llandovery or Penkill beds, Penwhapple Glen, 



Girvan. Coll. of Mrs. R. Gray. (P. 180.) 



14, 15. ,, Mullockiensis, Dav. External cast and interior of the dorsal valve» 



Lower Llandovery, Mullock Hill, Girvan. Coll. 

 of Mrs. R. Gray. (P. 180.) 

 16 — 18. Orthisina adscendens, Pander. 16, 16 a, b. Complete specimens showing the 



dorsal valve. 17. Ventral valve. 18. Interior of 

 dorsal valve. Upper Caradoc, Bwlch-y-Gossi beds 

 near Cynwyd. (P. 175.) 



19. Binobolus? IIicksii,T)diV. Upper Arenig, St. David's. (P. 212.) 



20. „ Davidsoni, Salter. Lower Wenlock or Upper Llandovery, Uggool, 



near Ballaghadereen, County Mayo, Ireland. 

 Museum of Geol. Survey of Ireland. (P. 212.) 

 21 — "23. Acrotreta Nicholsotii, Dav. 21. Llandeilo, Craighead. 22. Same formation, 



Balcletchie. 22. Ardmillan Brae. All in the 

 Girvan district and coll. of Mrs. R. Gray. 

 (P. 213.) 



24. „ ? costata, Dav. Llandeilo, Balcletchie. Coll. of IMrs. R. Gray. 



(P. 213.) 



25, 26. Obolella sagittalis, Salter. Llandeilo, Cairn Burn, Druidhill Burn, Dumfries- 



shire. Coll. Geol. Survey Scotland. (P. 211.) 

 27, 28. „ Sabrina, Callaway. Tremadoc (Shineton shales, Shineton, Salop). 



(P. 211.) 

 29, 30. Jcrof/iek(;/ranu/ata, himmi'sson. Llandeilo, Coalpit Bay, County Down, Ireland. 



Figures much enlarged. (P. 214.) 

 31 — 33. Siphonotreta scoiica, Dav. Llandeilo, Craighead, Girvan, and coll. of Mrs. R. 



Gray. (P. 217.) 



