102 



:nervous system of arthropods. 



more special auditory perception. On the other hand, 

 it is quite possible that sounds not appreciable by our 



Fig. 40. 



U' 



7 



Fig. 39.— Nervous System of full-grown Catei-pillar of Privet Hawk-Moth (Sphinx 

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



Fig. 40.— Nervous System of the Privet Ilawk-Moth thirty days after changing tc 

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

 bearing five instead of seven gangha. 



fio. 41.— Nervous System of the perfect Insect, a, Greatly enlarged cerebral, 

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

 respiratory nerves, ' ncrvi transvcrsi.' (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 



