254 THE STRUCTURE AND LIFE OF BIRDS CHAP. 
In Mr. Muybridge’s! 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 cither for stopping 
or striking. 
Fic 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 
' See Mr. Muybridge’s Anémal Locomotion, to be seen at the 
Brit sh Museum, 
