380 PROCEEDINGS OP THE GEOLOGICAL SOCIETY. [April 8, 



that in mountainous tracts torrential rivers and their feeders may- 

 have descended in past times as they do now, and may thus have 

 produced rounded materials in valleys, the argument is, at all events, 

 perfectly inapplicable to the formation of the Swedish osar. These 

 linear ridges have not only been accumulated in long trainees and 

 lengthened mounds or terraces high above the valleys, and offering 

 appearances entirely unlike those produced by rivers, but it is at 

 the same time evident, from the most casual inspection of the coun- 

 try, that as it now contains no torrents (all its streams being gently- 

 gliding waters which merely connect inosculating and long lakes), 

 so in the period immediately preceding our own, when the relations 

 of outline must have heen, pari passu, the same which now prevail, 

 no such river torrents can have acted in the level and undulating 

 countries of Sweden. But even this refutation is uncalled for, since 

 large portions of these flat countries offer indisputable proof in their 

 included marine shells of having been beneath the sea during the 

 accumulation of water-worn gravel and sand-banks, which extend 

 over at least ten degrees of latitude. 



In studying phaenomena more deeply seated than those under 

 consideration, the phaenomena on which the very elements of sound 

 geology now rest, a few years only have elapsed since the scientific 

 world was agitated by Wernerian and Huttonian theories, neither 

 of which, when exclusively considered, have proved to be entirely 

 true, but which, when combined, have been found to harmonize 

 Avith the observed laws and order of Nature ; and so, if I mistake 

 not, will it be with the glacial and aqueous transport of materials 

 over the surface of the globe, each of which will be found to have 

 performed its due part in bringing about those superficial appear- 

 ances ; for it seems unphilosophicad, if not impossible, to attempt to 

 explain them all upon any one hypothesis. In apportioning, how- 

 ever, to each of these causes its true effects, I doubt not that in 

 regarding the surface of the globe, we must look to the action of 

 water as of infinitely wider operation than that of ice. 



In concluding this memoir, I beg to add, that the conclusions at 

 which the distinguished naturalists, Owen and Edward Forbes, have 

 recently arrived, as drawn from their researches into the causes of 

 ancient zoological and botanical distribution from common centres, 

 seem to harmonize strikingly with my own views and those of my 

 colleagues as expounded in the work on Russia or as developed on 

 this occasion. Professor Owen has given reasons, which to my 

 mind prove to demonstration, that the British Isles must have been 

 connected as dry and habitable land with the continent of Europe, 

 when the large mammalia of lost races, as well as many quadrupeds 

 still living among us, were extended into our country. Professor 

 E. Forbes, on the other hand, has shown* that the occurrence of 

 certain isolated groups of Scandinavian plants on the summits of 

 some of our mountains can be best accounted for by the floating of 

 icebergs, which transported plants and seeds as well as northern 



* Memoirs of the Geological Survey of Great Britain, vol. i. p. 336. Professor 



