462 Dr. C. I. Forsyth Major — Rodents of W. Mediterranean. 



rivers, and so long as this outpouring has taken place so long must 

 the salinity of that sea have been greatly lowered. I have no doubt 

 that the migration of the Tapes fauna northward was due to the 

 inrush of the fresher water from the Baltic, which first poured out of 

 it in any great quantity when the great Baltic breacli occurred. 



From this evidence it is plain that the Western Baltic and its 

 three waterways furnish complete confirmation of the conclusion 

 forced upon us by the evidence of the Eastern Baltic, namely, that 

 the land-bridge once separating the Cattegat fiord from the great 

 Ancyltis sea was broken down in the human period, and, as the 

 vpestern evidence shows, after the period when the kitchen-midden- 

 men lived in Denmark. 



The same evidence also points to the breakdown having been rapid 

 or sudden, for, so far as we know, there is no evidence of the gradual 

 dwarfing and distortion of the oysters and the Tapes, but they went 

 out of existence when in full prosperity, as if the cause of their death 

 and extinction was a catastrophe. We can hardly resist the further 

 conclusion that during the period when the kitchen-midden-men 

 vsrere laying down their refuse heaps, the Baltic was a fresh-vpater 

 inland sea, and the Cattegat was much salter than now, with a salinity 

 and a zoological and botanical facies very like those of the present 

 Skagerack and North Sea ; and that these same men could then pass 

 to and fro over a continuous land-bridge into and from Skane in 

 South Sweden dryshod, and without any necessity for boats. 



Ereata in previous Papers. 

 Page 316, line 25, for at Rordam read as Eordam says. 



Page 411, line 30, for Skalbarende and udbredningsfolhold read Skalbserende and 

 udbredningsforhold. 



V. — EODENTS FROM THE PLEISTOCENE OF THE WeSTEEN 



Mediterranean Eegion. 

 By Dr. C. I. Forsyth Major, F.Z.S. 

 I. Geographical Distribution of Prolagus, a Tertiary type of Mouse- 

 Hares (Ogotonida), during the Pleistocene. 



IN a former publication^ I have dealt with the anatomy of Prolagus 

 sardus (Wagn.), from the Sardinian and Corsican Pleistocene, 

 in comparison with that of its Tertiary relatives. The following 

 pages deal with the geographical distribution of Pleistocene Prolagus 

 and its bearing on more general questions. 



When Cuvier discovered, in the ossiferous breccia of Corsica, 

 remains of a ' Lagomys,' which he believed to be closely related 

 to the Siberian Lagomys alpinus, he also suggested other analogies 

 between the faunas of the two regions — Siberia and Corsica (as well 

 as Sardinia), and commented upon the supposed relationship between 

 the insular Mouflon and the Siberian Argali.^ Similar views were 

 expressed by E. Wagner.^ 



^ Forsj'th Major, "On FossO and Eecent Lagomorpha " : Trans. Linn. Soc. 

 Lend. (2), vol. vii, pp. 433-520 (1899). 



2 " Ossements fossiles," vol. iv, pp. 201, 202 (1823). 



3 Denkschr. d. Miinchner Akademie, vol. x, p. 783 (1832). 



