44 EXTINCT BRITISH ANIMALS, 



average of five feet of snow on the ground (although, 

 of course, not evenly distributed), which means a 

 rise of at least two feet of water in the ponds and 

 lakes at the break-up of winter. How then would 

 a Beaver manage this superabundance of still water ? 

 You will probably say. " that's best known to the 



CRANIUM OF BEAVER FROM THE FENS. LTTER SURFACE, (g NAT. SIZE.)* 



Beaver himself!" Just so ; but we know what a 

 Beaver does under similar circumstances when he 

 has built his house and dam on a running brook. 

 During the summer months Beavers often frequent 

 ponds and lakes at a distance from their houses for 

 the purpose of feeding on the stems and roots of a 

 pond lily (Nupliar advena). When a Beaver's house 



* From a specimen in the Museum of the Eoyal College of Surgeons. 



