MAMMALIA 



125 



Japan, and also from the Pyrenees to the Caucasus. Other 

 species of hare are found in various parts of Asia, Africa, North 

 America, and South America. 



Pikas, or Calling Hares, are small creatures somewhat re- 

 sembling guinea-pigs, apparendy devoid of tail, and with rounded 

 ears of small dimensions. They are gregarious, and, failing 

 fissures in the rocks, , 

 excavate burrows. Most 

 of the species inhabit 

 the north and central 

 parts of Asia, one of 

 these, the Siberian Pika 

 {Lagomys Alpinus) (fig. 

 8 5), ranging into Eastern 

 Europe. There is also 

 one species in North 

 America. 



The three remaining |l|j' 

 groups of Rodents — i*'^ 

 Squirrels, Mice, and 

 Porcupines — agree with 

 one another, and differ 

 from rabbits and their 

 allies, in the number of 

 the incisor teeth, these 

 being only four in num- 

 ber, two above and two 

 below. 



2. The Squirrels 

 include forms in which 

 the bones of the lower leg (^tibia and fibula) are not united together. 

 Squirrels, Marmots, and Beavers are the representative types. 



Squirrels, as well seen in the Common Squirrel {Sciurus 

 vulgaris), our native species, have a rounded head, from which 

 large tufted ears project, a large bushy tail, and extremities 

 provided with sharp claws. The thumb is of very small size. 

 The range of this species includes the greater part of Europe, 

 North and Central Asia, and North Africa. Squirrels of one 

 sort or another are found in almost all hot and temperate coun- 

 tries, Madagascar and Australia excepted. Ground- Squirrels, 



Fig 85 — The Siberian Pika [Lagomys Aljfinus) 



