102 



NERVOUS SYSTEM OF ARTHROPODS. 



more special auditory perception. On the other hand, 

 it is quite possible that sounds not appreciable by our 



V 



Pio. 39. Nervous System of full-grown Caterpillar of Privet Hawk-Moth 

 igustri), about two days previous to its change to the chrysalis state. 



FIG. 40. Nervous System of the Privet Hawk-Moth thirty days after changing to 

 the chrysalis state. The abdominal cords are now seen to be much shortened, and 

 bearing five instead of seven ganglia. 



FIG. 41. Nervous System of the perfect Insect. A, Greatly enlarged cerebral, 

 and B, optic ganglia. The numerals refer to the numbers of the ganglia, o, o, o, o, 

 respiratory nerves, 'nervi transversi.' (Solly after Newport.) 



organization may be perceptible by the sensory organs 

 and centres of some of the lower organisms. 



Additional sensory endowments like Smell and Hearing 



