LOCALITIES IN " SILURIA." 99 



which yielded to their hammers no less than three species of fossil Fishes, Cephalaspis 

 Murchisonii, C. ornatus, and Auchenaspis Bgertoni, which Sir P. Egerton informs me is a 

 different species of Auchenaspis to that found at the Ledbury section outside the Tunnel. 

 At the Tin Mills, in this olive shale, no less than three species of Eurypterus were found, 

 together with the Pterygotus BanJcsii of the Kington beds. 



Purple grits full of mica succeed these shales at the Tin Mills, and they contain a 

 large Lingula. 



Over these again rests a grey micaceous sandstone, with Lingulce and carbonaceous 

 markings. These strata are upon nearly the same horizon as the grey Auckenaspis grits 

 of Ledbury. 



8. — Passage-beds at Ledbury, Herefordshire. 



In my paper on these rocks as displayed on the line of railway between Malvern and 

 Ledbury, in and outside the Ledbury tunnel, the following passage occurs : ! — " In my 

 communication on ' The Old Red Sandstone of Herefordshire,' published in the 

 'Edinburgh New Phil. Journ.' (April 1, 1859, p. 232), I expressed my opinion that 

 the Ludlow sections on the horizon of the Passage-beds above the Downton Sandstone are 

 broken by faults, and that the true succession is therefore destroyed. I had come to this 

 determination long before the beds now developed in the railroad-cutting at Ledbury 

 were exposed to view ; and, having again visited Ludlow, and compared the Passage-rocks 

 of that district with those of Ledbury, I am convinced that nowhere perhaps in the world 

 is there such an exhibition of Passage-beds presented to the eye of the geologist as at the 

 Ledbury Tunnel on the Worcester and Hereford Railway." 



I have visited Ludlow on more than one occasion since writing these words, and as I 

 have no reason for altering my opinion, I do not hesitate to reproduce the Ledbury section, 

 marking more especially the beds in which the remains of Crustaceans occurred. It 

 will be sufficient to say here that the section was entire throughout, not being interfered 

 with by any break or obscurity, and was carefully measured off yard by yard and inch by 

 inch. The Aymestry rock, with Pentamerus Knightii, was cut through in the Tunnel, 

 and was apparently higher in the Ludlow series than the Pentamerus Knightii rock of 

 Leintwardine. Thus we had — 1. Aymestry rock (ten feet) ; 2. Upper Ludlow beds with 

 Chonetes lata, &c. (140 feet; Ludlow Bone-bed not detected); 3. Downton sandstone 

 (nine feet), with Lingulce and fragments of carapace of Pterygotus ; 4. Red and mottled 

 marls and thin sandstones (210 feet), with Lingula and remains of Pteraspis ; 5. Grey 

 shales and grits at the tunnel's mouth (eight feet), with Pterygotus and Cephalaspis 

 Murchisonii ; 6. Purple shales and thin sandy beds (thirty-four feet), with a few remains 

 of Lingulce ; 7. Grey marl, passing into red and grey marl and bluish-grey rocks [Auche- 



1 'Quart. Journ. Geol. Soc.,' vol. xvi, p. 193. 



