CONTENTS. Vll 



PAGE 



ORGANS OF SENSATIONS. 



Brain and spinal cord in man . 75 



Main nervous stem in insects . ib* 



The ganglionic system in man . . 76 



A nerve-knot or ganglion described . . ib. 



Ganglionic brain in insects . ib. 



Differs from the ganglia and from the brain in man ib. 



Gullet ring and second ganglion . . . 77 



Third ganglion and others . . . ib. 



Number of ganglia . . ../;. 



Structure of an insect ganglion . ib. 



Nerves from the ganglia . . . ib. 



Structure of the nerves . 78 



Insects have not acute feeling . . 79 

 THE SENSES. 

 The sense of touch. 



The ears mistaken for organs of touch . ib* 



The feet, feelers, and hairs as organs of touch . 80 

 The sense of taste. 



Sense delicate, but the organ unknown . ib. 

 The sense of smelL 



The organ probably in the composite spiracles . ib. 



Singular opinion of Dumeril . . ib. 

 The sense of hearing. 



The ears often misrepresented . ib. 

 The sense of vision. 



The nerves of the eyes . 81 



The air-pipes of the eyes . . ib. 



Ants not blind . . 82 

 ORGANS OF REPRODUCTION. 



Insects differ from snails, and resemble birds . ib' 



Singularities in bees, wasps, and ants . ib. 



