1 84 



VETERINARY PHYSIOLOGY 



directly stimulated, and in showing no signs of hunger or of 

 thirst. A worm crawling in front of it 

 does not cause the characteristic series of 

 movements for its capture which are 

 seen in a normal frog. 



(2) In the pigeon (fig. 96, B\ removal 

 of the cerebral hemispheres reduces the 

 animal to the condition of a somnolent 

 reflex machine. The bird sits on its 

 perch, generally with its head turned 

 back, as if sleeping. If a sudden noise 

 is made, if light is flashed in its eye, or 

 if it is touched, it flies off its perch 

 and lights somewhere else. Clapping the 

 hands and letting peas fall on the floor 



Fig. 95. A, Section of cerebral cortex in the pre-Rolandic lobe a motor area ; 

 on the left, under a low power to show tlie distribution of the cells ; on the 

 right, a few of the cells from each zone more highly magnified. (For 

 description of zones, see text.) B, Section through Cerebral Cortex in the 

 region of the calcarine fissure (visual area), stained to show the arrangement 

 of the fibres (Human). (For description of zones, see text.) (CAMPBELL.) 



