INTRODUCTION. 5 



THE LEG AND FOOT. 



A bird's leg may be briefly described as having only the knee downward exposed ; 

 the true thigh is concealed, but may be felt under the skin on the side of the body. 

 The true knee is close to the body just under the skin. The first exposed joint which is 

 apparently the knee, but which bends back- 

 ward, is really the heel. (See illustration.) 

 The bird does not walk on the foot (from 



the heel downward), but merely walks on y ^^ ' ^^ B 



his toes. 



Reticulate Tarsus 



Booted Tarsus Scutellate Tarsus 



The Tarsus, which is measured from the bend of the leg (end of tibia) to the roots 

 of the toes (C to D in illustration) , is an important factor in the identification of 

 many species. The feet are very variable in shape and arrangement of the toes. 

 These variations are of the greatest importance, representing generic and, often, 

 family differences. 



Types of Feet. Water Birds. 



