2/6 HISTORY OF THE EUROPEAN FAUNA. 



In later miocene times the sea does not seem to 

 have surrounded the Alps to the same extent as it 

 did before, but it certainly extended from the Eastern 

 Alps to the shores of the Sea of Asov, so that the 

 direct northward passage was still more or less barred 

 to the Oriental immigrants. At the same time Alpine 

 species were now able to emigrate to the North 

 European provinces. During the last stages of this 

 epoch, the same sea increased its area very consider- 

 ably in an eastward direction. One continuous 

 expanse of water now stretched from the Alps as 

 far as the Sea of Aral in Central Asia, perhaps even 

 farther. 



During pliocene times especially, the northern parts 

 of the Balkan peninsula were occupied by a series of 

 freshwater lakes, while Greece was joined to Southern 

 Italy, Sicily, and Tunis. Central and Northern Italy 

 were represented by a long narrow peninsula con- 

 nected in the north with the Alps. Corsica and 

 Sardinia were joined to Sicily, and the Straits of 

 Gibraltar did not exist. When I first published my 

 views regarding these geographical conditions of the 

 Mediterranean area, Professor Deperet was good 

 enough to send me his criticisms from a purely 

 geological standpoint. He is of opinion that though 

 Sicily and Sardinia might at this time have still been 

 connected with Tunis, the Straits of Messina must 

 already have been formed in other words, Southern 

 Italy and Sicily could no longer have been connected 

 with one another. This opinion is based upon the 



