142 



Papers from the Department of Marine Biology. 



The amount of activity and metabolism in the muscles if they have 

 any noticeable influence on the rate of regeneration ought to produce 

 a clearly demonstrable result, but as shown by the data in table 3 

 and figure 8 the difference is relatively small. From the point of view 

 of the chemical nature of metabolism (including regeneration) the 



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FIG. 8. Showing rates of regeneration of activated and inactive 

 half-disks. The upper line represents the activated and the 

 lower line the inactive specimens. The divisions along the 

 abscissa represent regeneration in millimeters; those along the 

 ordinate represent time in days. 



difference in temperature might conceivably be sufficient to account 

 for the observed difference in rate of regeneration. The half-disks in 

 which the circuit wave is maintained show a greater regularity in the 

 rate of regeneration than do the active disks recorded in table 1. 



Further demonstration of the influence of the sense-organs on the 

 rate of regeneration is furnished in another series of experiments in 

 which the two insulated halves of a disk are compared, one of which is 



