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University of California Puhlications in Zoology [Vol. 18 



removed; so the nerve could rest on its own body fluids. In all these 

 cases coordinated movements of anterior and posterior portions were 

 shown. The best records were obtained when the least dissection was 

 used. 



The clinching argument, however, Avas obtained when during the 

 course of such experiments the nerve cord is cut. In all such cases, no 

 matter what type of dissection was used, non-coordinated movements 

 were shown when the cord was transected (fig. 7). 



ant. 



post. 



Fig. 7. Experiment 143. Explanation of the curves here the same as in 

 figure 6. The nerve cord connection between anterior and posterior has been 

 cut. Notice the lack of coordination between the movements of two portions 

 of the worm. 



(c) Stovaine. Should any doubts still remain concerning trans- 

 mission of impulses for locomotor movements over long sections of the 

 nerve cord, the action of stovaine will set these completely at rest. If 

 stovaine be injected into the body cavity of the worm it acts as a block 

 to the nerve cord over four or five segments and allows no impulses to 

 pass up or down through the segments containing the anesthetic. The 

 records will show that there is a lack of coordination and suppression 

 of movements of the posterior end while the drug is effective (fig. 8), 



