94 Charles Zeleny. 



The general result is clear. The regenerated cutting chela is 

 larger in the case where two chelae are regenerating than where 

 one alone is to be replaced. This result is emphasized by the 

 fact that the time between the first two moults is shorter in the 

 specimens with two chelae removed than in those with only one 

 gone. (See p. 87.) 



3. Discussion. 



The significance of the data may be emphasized by bringing 

 them out in two ways, one of which lays special stress upon the 

 fact ot removal of a certain organ or organs and the necessity of a 

 certain amount oi regulation in restoring the normal form, and 

 the other of which emphasizes rather the interactions of the two 

 chelae as parts of a system normally stable at the condition with a 

 large snapping chela on one side and a small cutting chela on the 

 other. 



The first point of view in which the total necessary amount of 

 regulation is compared with the rate of regeneration of a part of 

 the whole will first be taken up. The three series of experiments 

 may be compared in the following way: 



1. With the cutting chela alone gone the animal has merely to 

 accomplish the regeneration of this organ in order to regain its 

 normal condition. 



2. With the snapping chela alone gone the animal has not 

 only to regenerate a cutting chela in place of the old snapping one 

 but also to differentiate the tissue of the old cutting chela into the 

 new snapping chela. 



3. With both chelae gone the animal has not only to regenerate 

 a new cutting chela in place of the old one but also to regenerate a 

 new snapping chela. 



Taking the ratios given in Table XVI, p. 93, we see that in 

 the first case where the least work is to be accomplished, at the 

 end of the first moult the cutting chela has regained but 59.3 per 

 cent of its original size, while in the second case it has reached 66. i 

 per cent, and in the third case 74.5 per cent of its original size. At 

 the end of the second moult likewise we have, respectively, 74.3 

 75.1 and 87.0 per cent for the three cases in question. 



Therefore, the amount, of actual regeneration accotnplished in 

 the cutting chela is greater the greater the amount of other work 

 of a similar character to be accomplished at the same time. 



