254 The Rev. A. Sedgwick's Outline of 



The author then gives the subjoined lists of fossils from different 

 localities on the lines of the sections above noticed. It is a mere 

 synopsis of the fossil evidence, but has been carefully made out by 

 Mr. J. Sowerby ; and by Mr. J. W. Salter, who accompanied the 

 author in his last examination of the country along the line of the 

 Holyhead road. 



List of Fossils from several localities in tlte middle division of the 

 Cambrian Slates. 



I. 



Penmachno and Conway 



Falls. 

 Trinucleus Caractaci. 

 Asaphus Tyrannus. 

 Leptsena sericea. 

 Orthis canalis. 



testudinaria. 



— — alternata. 



Actonise. 



Tentaculites scalaris. 



II. 



Hills opposite Bettws-y- 

 coecl. 



Crustacea. 

 Trinucleus Caractaci. 



Heteropoda. 

 Bellerophon bilobatus. 



Brachiopoda. 

 Leptsena sericea. 

 Orthis canalis. 



testudinaria. 



— — alternata. 



Actonise. 



flabellulum. 



new (very convex) 



(half a mile above Con- 

 way Falls). 



III. 



Cerrig y Druidion. 

 Orthis alternata. 



new (abundant). 



Ophiura Salteri. 



IV. 



Glyn Diffwys and Cader 

 Dinmael Limestone. 



Crustacea. 

 Tails of a Calymene. 

 Asaphus Powisii. 

 ■ Tyrannus. 

 Trinucleus Caractaci. 

 Brachiopoda. 

 Leptsena tenuistriata. 

 sericea (abundant). 



Spirifer crucialis (new). 



Orthis Actonise (do). 



Vespertilio (do). 



— — virgata (abundant). 



— — canalis. 



Radiata. 



Favosites polymorpha. 



Round coral. 



Hemispherical coral 

 (new ?), and several 

 other species of corals 

 and shells. 



V. 



Sandstone bed on Cader 

 Dinmael {scarcely ex- 

 amined). 



Crustacea. 



Brachiopoda. 

 Orthis flabellulum (abun- 

 dant). 

 — — canalis. 



CONCHIFERA. 



Avicula, n.s. 

 VI. 

 Bala Limestone. 



Crustacea. 

 Tails of a Calymene. 

 Brachiopoda. 

 Leptsena tenuistriata(none 



of sericea). 

 Spirifer crucialis. 

 Orthis Actonise (do.). 



Vespertilio (do.). 



canalis. 



virgata (abundant). 



Radiata. 

 Round coral. 

 Hemispherical coral. 

 Tentaculites annulatus. 



VII. 



Calcareous Slates of Bala, 

 Gelli Grin, §c. 



Crustacea. 

 Trinucleus Caractaci. 



The fossiliferous series above described is called the great proto- 

 zoic group of North Wales. It is stated, that there is no good fossil 

 evidence for its separation into distinct formations ; and that its in- 

 ferior beds, although far below the Caradoc sandstone, contain com- 



Brachiopoda. 



Leptsena tenuistriata. 



sericea (very large). 



Spirifer radiatus, M. C. 



crucialis? 



Orthis flabellulum. 



Vespertilio. 



canalis. 



alternata. 



— — virgata. 



MOLLUSCA. 



Turbo Pryceae. 



• angulatus 1 



Euomphalus sculptus 1 



Radiata. 

 Ophiura Salteri (pelvis). 



VIII. 



Slates. South of Llansaint- 

 fraid Glyn Ceiriog. 

 Crustacea. 

 Trinucleus Caractaci. 

 Calymene (tail). 

 Asaphus caudatus ? 



Powisii. 



Brachiopoda. 

 Leptsena tenuistriata. 



sericea. 



Orthis inflata (new). 



canalis. 



alternata. 



Actonise. 



Radiata. 



Turbinolopsis bina 

 (abundant). 



IX. 



LlansalntfraidLime.ston.es 



and Shales. 

 Leptsena sericea. 

 Orthis canalis. 



Actonise. 



Euomphalus (new). 



Radiata. 

 Catenipora escharoides 

 (abundant), and many 

 others. 



