BILL~OF THE NUTHATCH. 197 



tip ; but they differ considerably in form with the places 

 where the food is obtained, and in consistency with the 

 nature of the food itself. They are bark birds, wall 

 birds, or rock birds, yet some of them range the air 

 for their food, and others seek it in the nectaries of 

 flowers. The feet rather than the bill form their 

 distinguishing character. The nuthatch , which is a 



Nuthatch. 



climber, has the bill straight, angular, and very strong, 

 and it feeds much upon nuts, the shells of which it 

 punches open with considerable activity. The tree 

 creepers which also run on the boles of trees, and 

 dig in the crevices of the bark for insects, have the 

 bill of moderate length and angular, but a little curved. 

 The wall creepers have it very long and slender, and 

 angular only at the base. The nectar suckers have 

 the bill weak and very slender at the tip, and the 

 tongue extensile, tubular as a sucker, and cleft at the 

 tip. The humming-birds have the bill in general 

 long, and the tip of the tongue formed as a sucker ; 

 but the bill is in some of the species straight, and in 

 others crooked. The hoopoe has the bill very long 

 and slightly arched, and feeds on tadpoles and other 

 produce of marshy grounds. But the bills of these 

 birds are so unlike in their forms, and differ so much 

 in the uses to which they are applied, that none of 

 them can be taken as any thing approaching to an 

 average of the whole ; and indeed the character of 



