78 



INTERNAL ORGANS. 



the stomach, the air-pipes, and the muscles throughout 

 the body. 



Lyonnet counted forty-five pairs of these nerves, 

 and two single ones in the goat caterpillar, making 

 in all ninety-two, which is fourteen more than are 

 found in man. 



The double nervous chords uniting the ganglia are 

 tubular, and composed of two substances, the mem- 

 brane forming the tube, and a sort of marrowy sub- 

 stance with which this is filled. It is probable, that 

 the smaller branches are similar in structure. 



The nervous system in a garden beetle (Carabus}. a, the first 

 nerve-knot or ganglion, with a large nerve on each side going 

 off to the eyes ; b, the second nerve-knot ; c, the third, nerve- 

 knot 5 d, e, /, g, h, the other nerve-knots or ganglia, 



