8G2 T. BELT ON THE STEPPES OF SOUTHERN RUSSIA. 



lie found the Dreissena and a Cardlum-like shell in lakes near the 

 Danube. 



Prof. Morris said, with reference to Admiral Spratt's remarks 

 about the shells, that there were several distinct conditions to be 

 considered, and especially whether the shells were those of in- 

 habitants of lakes, rivers, or brackish water. The Dreissena and the 

 Cardhun-like shell referred to were modified brackish- water forms. 

 Then he should like to know whether the specimens of Planorbis 

 were mixed with the others, and, farther, what were the relations 

 of the shells found below the diluvium to those now living in the 

 same areas. 



Admiral Spratt stated that his Planorhes were certainly mixed 

 with the others, and that the shells found below the diluvium seemed 

 to him to be identical with those now living. 



Mr. Belt, in reply, said that most of the arguments brought for- 

 ward were already answered in his paper. Prom the marine Miocene 

 beds there was a regular sequence up to the freshwater beds with 

 Paludvia and Melanopsis. Then there was a great gap ; the waters 

 of the old Aralo-Caspian sea were lowered, and the above-mentioned 

 beds denuded. The next stage was the filling up of the basin again 

 by the waters from which the diluvial beds were deposited, and a 

 great destruction of life. He agreed in the main with Admiral 

 Spratt's remarks, and had studied the beds referred to by Prof. 

 Judd, which he considered were just such as would be formed at 

 the mouths of streams emptying into a lake. 



In regard to river-basins, he agreed with Prof. Prestwich that 

 much might be said in favour of their agency in the deposition of the 

 gravels and clays that fringe their valleys ; but in Russia the dilu- 

 vium covers the whole country, and extends across the watersheds. 

 The northern blocks have been carried in the opposite direction to 

 the flow of the northern rivers ; and for their transport a wide sea- 

 like expanse of water is required. 



The President remarked that Sir Joseph Hooker, who first wrote 

 on the Himalayas in connexion with the present subject, had stated 

 that there is a complete absence of glacial striae, which is, no doubt, 

 due to rapid waste. Por himself he had been startled by the 

 amount of life proved to exist within 15° or 16° of the North Pole 

 in shallow water ; and Dr. Giinther had recently described a 

 species of Char from a lake which is frozen for many months in 

 the year. 



