254 THE STRUCTURE AND LIFE OF BIRDS chap. 



In Mr. Muybridge's 1 photographs of a Cockatoo on 

 the wing, both bastard wings may be seen to be slightly 

 raised, for what purpose it is hard to say. In the 

 Pigeon too they project during a vigorous stroke, but 

 I have seen no other bird use them either for stopping 

 or striking. 



Fig 65. — Drawn from a photograph by Ottomar Anschutz, showing bastard wing 

 extended during downstroke. 



The Centre of Gravity. 



In the bird the centre of gravity falls at a point low 

 down in the body : the heavier organs are accumulated 

 there, the lighter ones up above. Below are the great 

 breastbone and the ponderous muscles of flight (the 



1 See Mr. Muybridge's Animal Locomotion, to be seen at the 

 Brit sh Museum. 



