Sir H. H. Hoivorth — The Baltic — The Litorina Sea. 319 



that sea in ancient times than now. Lomberg has analyzed the 

 conditions of the present currents of salt and fresh water in that 

 sea with considerable lucidity, and makes it dependent on the 

 present submarine banks and reefs which cross that sea and which 

 interfere with the nether currents, conditions which would of course 

 not be present in the same degree when the general depth of the 

 water was greater. Thus he says : " The southern sill and the 

 narrowing between Saltholm and Scania cause the brackish currents 

 from the Baltic to reach right to the bottom ; but as the Sound 

 widens again these currents broaden and thin out so that their 

 effects do not stretch so deep. Thus the bank between Malrao and 

 Saltholm forms a complete barrier against the marine forms, the 

 southern end of the Sound is occupied by a brackish-water fauna, and 

 the limit between this and the deeper salt-water fauna gradually 

 rises nearer the surface as it approaches the northern end of the 

 Sound " (Lomberg, Meddelanden fram Kong. Landb., pp. 43, 44, 

 trans, by Bather, Nat. Science, xv, 269). Munthe has applied the 

 same form of reasoning to the conditions of the Baltic in the Litorina 

 time. Thus he says : " The condition of things was of course most 

 favourable for the transfer of salt water from the Cattegat to the 

 Baltic at the stage when the land subsidence in the Litorina time 

 had reached its maximum .... Kemembering that the Baltic 

 basin's bottom at the Litorina time lay comparatively deep below 

 the surface of the ocean, we can see that, especially at the stage of 

 greatest subsidence, the salt currents from the Cattegat must have 

 been able to force their way much more easily than at present, 

 even across the bars, hidden under water, that are to be found in 

 the district both at the boundary between the Bothnian Gulf and the 

 Baltic and in North Quarken. As the results of the Ekraan expedition 

 in 1877 show, these hidden bars, lying now at a depth of less than 

 40 metres, hinder to an appreciable extent the influx of Salter 

 under-currents. This cannot have been to the same extent the 

 oase in the Litorina time, for the bars then lay at a considerably 

 greater depth, viz., at a depth of about 90 and 130 metres 

 respectively." This seems to be a quite rational and adequate 

 explanation of the decreasing salinity of the Baltic. 



In concluding this paper may I add a word about another matter 

 of some importance. In recent years strong efforts have been made 

 by some, and notably by Professor Suess. to show that the alleged 

 changes of level in sea and land round the Baltic has been due to 

 a shifting of the water-level due to aberrant influences, and not to 

 any alteration in the earth's crust. 



The evidence of the Litorina beds seems quite inconsistent with 

 this conclusion, for they are neither at the same level nor do they 

 culminate in height in a regular gradation in any direction ; but on 

 the contrary they culminate to a point, i.e. the neighbourhood of 

 Hernosand, in the Central Baltic, from which they fall away both 

 north and south. This is not all. 



The fact that the level at which the so-called Litorina deposits 

 occur increases considerably as we proceed from the Baltic towards the 



