XI.] GENERAL PROPERTIES OF NERVOUS TISSUE. 117 



c. There are no respiratory movements, either 

 of the nostrils, or of the throat. 



2. Gently pull out one of the hind-limbs, until it 

 becomes quite straight, and then let it go. It 

 will be immediately drawn up into its old posi- 

 tion under the body. If this experiment be 

 made soon after the operation of removing the 

 brain, or if much blood has been lost, the leg 

 may be drawn up slowly instead of sharply. 



3. Gently tickle one flank with a feather or a blunt 

 needle; a contraction of the flank muscles of 

 that side will be observed. 



4. Pinch the same spot rather sharply with a pair 

 of forceps ; the leg of the same side will be first 

 extended, and then drawn up and swept over the 

 flank, the movement tending to thrust away the 

 points of the forceps. 



5. Pinch with the forceps the skin round the anus ; 

 both legs will be drawn up and thrust out again; 

 the movement tending as before to sweep away 

 the points of the forceps. 



Leave the animal alone for five minutes and 

 watch it carefully: if no disturbing circumstances 

 are brought to bear on it, it will remain perfectly 

 motionless. 



6. Place the animal on its back ; it will make no 

 effort to regain its normal position, i.e. all sense 

 of equilibrium has been lost. 



