9 
BEAUTIFUL BIEDS. 
feet of any of the Scansores ; for, when assisted by 
their hill, they can not only climb, bnt feed with their 
feet, this latter faculty being denied to all other 
groups. The Toucans, Cuckoos, and Puff-birds have 
the arrangement of the toes like unto the Parrots, hut 
there is no breadth of sole, the tarsus is much more 
lengthened, and the toes, instead of being thick and 
strong, are slender and weak. These hmds never 
climb, hut as they sit much and often very long upon 
branches, it is necessary that their feet should be of 
such a form as to enable them to preserve an equal 
hold on all sides ; we accordingly term their feet 
grasping. The Trogons exhibit another modification 
of structure in their feet, then’ toes are placed two 
before and two behind, bnt the posterior ones are 
altogether incapable, from the manner of their inser- 
tion, of being moved from their ordinary position, and 
tliey might therefore be termed the only birds whose 
toes are absolutely in pairs ; but they are by no means 
scansorial birds, and as they are perhaps the most 
sedentary birds in creation, their feet, which are also 
the weaker, seem to be constructed for the sole pinpose 
of sitting still. These are termed gressorial feet.^ 
The true scansorial foot, according to Mr. Swainson, 
is seen only in the 'Woodpeckers. The toes of these 
bu’ds are arranged in pairs, and the outer hinder toe 
appears capable of a partial lateral motion, which 
assists the bird when climbing the bole of a tree. On 
flying from one tree to another, the Moodpecker 
generally alights upon the upright stem rather than 
upon a horizontal branch, and immediately begins, in 
* Classification of Birds. 
