James Geikie — On Changes of Climate. ' 255 



The upper deposit (3) is chiefly noteworthy for its enormous 

 thickness, otherwise it exactly resembles the moraines of the Swiss 

 Alps. The bed 2 also answers precisely to the Alpine diluvium 

 described by Morlot and others. It contains no fossils, and seems 

 to be composed of more or less rounded stones, irregularly stratified. 

 None of the stones are scratched, and no angular blocks occur 

 among them. Towards the upper surface of the deposit, however, 

 erratic blocks begin to appear, and the " diluvium " then assumes 

 the aspect of a moraine profonde. The underlying Sables Pliocenes 

 marins contain a number of fossils, of which the following are said 

 to be characteristic [the notes on the shells have been kindly 

 furnished by my friend Mr. Etheridge] : 



PanoptBa Faujasii (Menard) occurs in our Coralline Crag and Eed Crag, and is 



living in the seas of Sicily. 

 Fecten jacobceus ; not known fossil in British strata; a Mediterranean shell. 

 Fecten maximus (Linn) ; Coralline Crag and Eed Crag ; Drift ; living in British Seas, 



North Sea, and Mediterranean. 

 Area Noe (Mont.) =^. tetragona (Poll); Coralline Crag and Eed Crag; living in 



Scandinavian and British Seas, and Mediterranean. 

 Murex saxatilis ; Suhappenine shell ; not known in Britain ; living in Mediterranean. 

 Murex JBrandans=M. triacanthus (Gmelin) ; Miocene shell; said to be living in 



Mediterranean. 

 Nassa conglobata (Broc.) ; occurs in Eed Crag, extremely rare ; a Miocene and 



Suhappenine species ; not known in our drift ; extinct. 

 Nassa prismatica (Broc.) ; Coralline Crag and Eed Crag ; not Glacial nor in any 



drift ; lives in the Mediterranean. 

 Natica millepunctata (Lamk.) Miocene shell ; lives in Mediterranean. 

 Ranella IcEvigata (Lamk.) =i2. marginata (Sow.) Miocene, (.'') living. (Much con- 

 fusion about this shell.) 



Eesting upon the marine sands which contain the above fossils, 

 occurs here and there an ancient alluvium, which is believed by Martins 

 and Gastaldi to be of older date than the alpine diluvium. This de- 

 posit has yielded remains of the Mastodon, the Ehinoceros, the Hip- 

 popotamus, etc., along with shells of such genera as Clausilia, Paludina, 

 and Helix. In the paper to which I am indebted for these details, 

 Martins and Gastaldi correlate this section with that at Diirnten, 

 and are clearly of opinion that the Italian " alluvium with bones " is 

 the equivalent of the slate-coal or lignite of Switzerland. But at the 

 time their paper was written, the interglacial character of the Diirnten 

 beds had not been ascertained. It is, therefore, possible that their 

 opinion on this point may have undergone some change ^ since that 

 discovery was announced : for, according to them, the marine sand 

 and freshwater alluvium of the plains of Piedmont are Pliocene, and 

 therefore preglacial. Many considerations, however, lead me to 

 believe that the correlation of the Italian and Swiss deposits, which 

 Martins and Gastaldi have made, need not be abandoned, notwith- 

 standing that the Diirnten beds have since proved to be of inter- 

 glacial age. 



It will readily be admitted that the vast changes of climate which 

 are indicated by the interglacial beds and associated deposits of 



^ In a recent memoir Gastaldi takes no notice of the Diirnten beds, and continues 

 to describe the Italian deposits as belonging to the Pliocene. [See Studii sulle 

 Alpi Occidentali ; Mem. del R. Comii. Geol. d'ltal., vol. i., 1871.] 



