IN GENERAL. 117 
or five ; one group alone has only four toes on all 
the feet. In all of them the two middle toes are 
longest and equal, and the two outer shorter; the 
fifth on the fore-feet is internal, and never reaches 
to the ground. Of the feet the toes only rest on the 
earth ; the claws are not retractile, but are strong, 
blunt, and fit for digging the ground ; the soles and 
end of each toe are furnished with tubercles. Several 
species, both in high and low latitudes, have the 
soles or tubercular part of the feet covered with hair. 
Near the arctic’ circle, Nature has conferred this 
protection upon some kinds of domesticated dogs, 
and even upon the red fox. It is a sort of glove. 
To which end, then, was it likewise bestowed upon 
several smaller species living near or within the 
tropics? This question is not yet determined ; but 
we may surmise that the fur is of a different struc- 
ture, and intended to enable the possessors to ap- 
proach their prey without noise or concussion of the 
-earth, of which small birds and insects are remark- 
ably sensible ; and, therefore, that those so provided 
are all to a certain extent insectivorous. 
Canines have two sorts of hair, an under fur of a 
soft woolly nature, and one of longer coarser piles 
forming the outer coat. The tail in general is long 
and hairy, reaching below the heel to the ground, 
or even more. Its muscular flexibility and action 
furnishes some slight additions for the separation of 
the different groups, and most naturalists agree with 
Linnzus in the assertion, that in domestic dogs it 
