326 



EUSSIA IN EUEOPE. 



of the same species as that of Lake Peipus, hunted by men for its fat and skin, 

 and preyed upon by wolves, which, when driven by hunger, will venture across 

 the ice to the middle of the lake. Some of the smaller animals, like the seal 

 itself, recall a time when Ladoga still communicated with the sea. One of these 



Fig. 175 — Ladoga. 



Scale 1 : 2.000,000. 



Depth in Fathoms. 



Under 13. 



13 to 27. 



27 to 55. 

 , 25 Miles. 



Over 55. 



.microscopic organisms, the CompylocUscKS radiosus, has hitherto been found else- 

 where only in the Gulf of Mexico, near Vera Cruz. 



The lake is sometimes swept by gales, which raise heavy seas, billows, and 

 ground swells like those of the ocean. Its waters are also kept in a constant 

 ferment by its tributaries, to which is perhaps partly due a current setting 

 steadily along the east coast northwards, and along the west coast southwards. 

 Its level has been determined by Schubert at about GO feet above that of the Gulf 



