CHAPTER XLIV. 

 ORGANIC REMAINS OF THE OLD RED SYSTEM. 



Introduction.— Fishes (Pis. 1, 2 and 2 bis.~)—MoUusca, fyc. (PL 3.) 



IT was a prevalent belief among geologists, when this work commenced, that few or 

 no animal remains existed in the Old Red Sandstone of England. I first undeceived 

 myself on this point by observing shells in the lower group or tilestones in Caermar- 

 thenshire, where they have been already alluded to (p. 183.). I afterwards discovered 

 similar fossils in the great outlier of Clun Forest (p. 191.). These remains which occur 

 in the very lowest beds only of the Great Red System are figured in PL 3. 



Subsequently my attention was called to other singular forms, which Dr. Lloyd of 

 Ludlow had discovered in the central parts of the system north of Ludlow, and in the 

 hills between Tenbury and Leominster. From the shield or buckler-shape of the most 

 remarkable of these bodies, some of the naturalists to whom they were first referred, 

 considered them to belong to crustaceans, an opinion, however, in which their discoverer 

 did not participate ; Dr. Lloyd having originally suggested, that the bony structure ap- 

 parent in some of the fragments appeared to exclude them from that class. The opinion, 

 however, that these remains might be Trilobites did not long prevail ; for when Mr. 

 Lyell received specimens of unquestionable, though undescribed fossil fishes from the 

 Old Red Sandstone of Scotland (1833), it was at once perceived by Mr. Lonsdale of 

 the Geological Society, that our shield- shaped bodies from Herefordshire and Shrop- 

 shire, were nothing more than the heads of the same singular genus of fishes, which 

 at that time had not been seen by M, Agassiz. After being thus convinced, that these 

 curious fragments really belonged to fishes, my geological examination during the fol- 

 lowing year brought forth similar remains from nearly every part of the great area oc- 

 cupied by the cornstone and marls of the Old Red Sandstone. Before the close of the 

 summer of 1833 I had, indeed, traced them through large tracts of Hereford, Salop, 

 "Worcester, Monmouth and Brecon ; and as they were always found in the same division 

 of the Old Red System, they had become valuable auxiliaries in enabling me to identify 

 subdivisions through England and Wales, and also to institute direct comparisons be- 

 tween the different strata of the Old Red Sandstone of England and Scotland. These 

 remains occur both in the impure and sandy cornstones, and in the larger sub-crystalline 



