118 THE STRUCTURE AND LIFE OF BIRDS CHAP 
animal’s part. In the same way when the eyes wink 
at a sudden flash of light, we call the ‘action reflex. 
The Frog, whose cerebral hemispheres are no longer 
in their place, will move its foot when it is irritated : 
of thus much, lower parts of the brain are capable 
elf 
c.& 
7 7t 
Fig. 30.—Prain of Pigeon (after Parker); A from above; B from below; C from 
left side (x2); erebellum; c.h. cerebral hemispheres; m.o. Medulla Oblongata; 
n roots of cerebral nerves 3 0.1. optic lobes ; olf olfactory lobes ; pn pineal body. 
If the whole brain is removed and only the spinal 
cord is left, even breathing will not continue. When 
there is much intellectual power, as in man, the 
hemispheres are highly convoluted—ze., they are a 
mass of folds and wrinkles, When the bird’s skull is 
