314 



ZOOLOGY. 



oblique flight than those which have the wings truncated at 

 the extremities. 



Thus the falcons (Fig. 288), which have the wings pointed, 

 rise only in zigzag, like a vessel tacking : whilst the hawk, 

 eagle, and other birds of prey, called base or ignoble, whose 

 wings are truncated at the extremities, can rise vertically 

 through the air. 



Fig. 290. Wing of the Sparrow Hawk.* 



In rising from the soil, the bird first springs or leaps from 

 the ground by means of his feet ; 

 if these (the limbs) be too short, 

 as in the case of the martinets, 

 they find it difficult to make the 

 first bound, and seek a declivity 

 to enable them to have room for 

 the expansion and action of their 

 wings. 



Birds in their flight are assisted 

 by the tail feathers, which seem 

 to act as a rudder in directing 

 their course. 



433. When resting on the 

 soil, the bird is strictly a biped, 

 and hence the necessity for a 

 broad and large pelvis, firmly 



Fig. 29i.-Pied Woodpecker ; xed *? &* vertebral column The 

 Picus. haunch bones are, in fact, ex- 



* a a, primary quills; J, secondaries. 



