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HITCHCOCK'S IN ATOMY 



of vital action must be very trifling. For the simplest office 

 of a nervous system is to establish a communication between 

 the different parts of the body ; but if every part of the body 

 has similar endowments, there can be no object in such com- 

 munication. For instance, where every part of the surface — 

 as is the case in those animals — is equally susceptible of ab- 

 sorption, there can be no need of a circulating system, and 

 w T here contractility seems to be diffused through the body 

 alike, a nervous system would be superfluous. 



671. What of the nervous system of Infusoria. 



