1 66 Lloyd's natural history. 



ority, we find their British representatives exceeding in this 

 respect the terrestrial members of any other Order belonging to 

 our fauna. 



With the exception of one South American species, existing 

 Rodents are mostly animals of comparatively small size, many 

 being very minute. Although some are aquatic, and others 

 arboreal in their mode of life, the majority are terrestrial. By far 

 the greater number are exclusively vegetable feeders, and 

 there are scarcely any which do not eat vegetable food of some 

 kind or other. Consequently they are, of all Mammals, the 

 most harmful to the agriculturist. 



Although the Order is divided into a very large number of 

 Families, only four are now represented in the British Islands, 

 two of which have but a single species each. Within the 

 historic period a fourth Family — the Beavers — was, however, 

 represented by its typical member within our area. 



THE SQUIRRELS AND MARMOTS. 

 FAMILY SCIURID^. 



Confining our attention throughout our description to the 

 British representatives of the Order, the Squirrels may be 

 defined as Rodents with cylindrical hairy tails, having cheek- 

 teeth furnished with roots and carrying tubercles on their 

 crowns, and by the presence of two pairs of pre-molars in the 

 upper, and one pair in the lower jaw, the first pair of upper 

 pre-molars being, however, often minute, and not unfrequently 

 shed at an early age. 



With the exception of Australasia, this numerous Family is 

 cosmopolitan in its distribution, and while its typical represen- 

 tatives — the Squirrels — are arboreal, the Marmots are terres- 

 trial 



