328 Horner's Geological Address. 



observations upon the action of floating ice upon the granitic 

 shores of the islands. All the rocks below h\gh-ivater mark^ and 

 some considerably above it^ are rounded off into long irregular 

 ridges^ with intervening hollows, by the half-floating masses of 

 ice.''' 



Paheontology. 



This great department of Geology is now cultivated with so 

 much industry by so many naturalists in Europe and America, 

 that scarcely a month elapses without some valuable additions 

 to our knowledge. It is not possible for me to do more than 

 briefly refer to some of the more important of those which I 

 have had an opportunity of becoming acquainted with. 



At the last meeting of the British Association at Cambridge, 

 Professor Edward Forbes made an interesting and important 

 communication to the Natural History section, in which he 

 pointed out a connexion of the present distribution of plants 

 with geological changes which took place during the later ter- 

 tiary periods. He maintains, for example, that the existing 

 flora of Britain belongs, not to the present epoch only, but is 

 composed in part of the remains of the floras of the pliocence 

 and post-pliocene periods. He considers that certain peculiari- 

 ties of the vegetation of the west of Ireland depend on an an- 

 cient geological connexion with the Asturias ; those of the 

 Scottish and Welsh mountains on the migration of plants from 

 Scandinavia during the glacial period, and the subsequent up- 

 heaval of the land, and consequent change of climate ; whilst 

 the great mass of the British flora migrated across the up- 

 heaved bed of the Pleistocene sea. He further holds, that 

 the determination of the date of the migrations of terrestrial 

 plants and animals will eventually aid in fixing the periods of 

 many geological events. 



In the year 1828, M. Elie de Beaumont published in the 

 '* Annales des Sciences Naturelles" an account of some obser- 

 vations he had recently made at Petit-Coeur, a village in the 

 Tarentaise, east of Chambery ; where he had seen resting on 

 talcose gneiss and hornblende schist, a series of sedimentary 

 beds, which prevail over a great extent of that country, the 

 lowest of which, a micaceous sandstone alternating with a 



