410 Townshend M. Hall — Fossil Fish in N, Devon. 



a low but abrupt cliff. Had the flow of ice been from the soutb, the 

 reverse would probably have been the case, and the low shelving 

 wedge-like shore, which forms a slide for the ice to mount together 

 with its load of boulders, would have been at the opposite extremity 

 of the island. On a rising area of this sort the impressions that 

 have been made appear certainly to affect in a permanent manner 

 even the contour of the island, and it does not seem unreasonable 

 that scratches and boulders may in a rising area be similarly pre- 

 served. Should the rising area be in a climate like that of Green- 

 land, the effects of coast-ice would in time be planed away by 

 glaciers. If the area be a sinking one, the results may be reversed. 

 The surface configuration of the land, whether produced by glaciers 

 or other causes, will be remodelled by the coast-ice, and these in 

 their turn, on reaching deeper water, will be affected by the 

 icebergs. 



Looking at the effects of ice-work in this way, we see that there 

 is a possibility of a sequence in their action. In high latitudes, 

 where the climate is a constant one, the sequence is definite. Should 

 the climate, however, be variable, we might have a surface scoured 

 by icebergs, and covered with debris not emerging from the sea, 

 until a warmer temperature had dissipated the icy pavement that 

 once floated, and in this way we might see the effects of icebergs in 

 the modelling of a land-surface. 



THE END. 



IV. — Fossil Fish in North Devon.^ 



Ey Townshend M. Hall, F.G.S., etc. 



THE recent discovery of fossil fishes in the Carboniferous beds of 

 North Devon appears of sufficient importance to require that 

 the facts connected with it should be placed on record. 



In the first place, it is necessary that I should give a short sum- 

 mary of what was known down to the end of the first week of 

 July, 1876, regarding the occurrence of fossil fish throughout the 

 northern division of the county. 



(1.) The Lynton, or Lower Devonian group affords remains which 

 have been referred to Steganodictyum, as well as fragments of fish 

 bones in considerable quantities. 



(2.) The Middle Devonian, near Tlfracombe, contains fish spines, 

 bones, and coprolites ; but owing to the absence of scales and teeth, 

 it is impossible to determine the genera to which they belong. 



(3.) In the Upper Devonian, at Baggy Point, a scale of JTolopty- 

 cJius was described and figured by Professor Phillips in 1841.^ 



(4.) In the Carboniferous formation, as far as I am aware, there 

 has been no single instance of fish remains, with the exception of 

 a doubtful fragment resembling a portion of a scale, found by me 

 some years ago at Venn Quarry, near Barnstaple. 



^ Eead before the Devonshire Association for the Advancement of Science, Litera- 

 ture, and Art, Ashburton Meeting, July, 1876. 



^ Palseozoic Fossils of Cornwall, Devon, and West Somerset, p. 133. 



