THE PHYSIOLOGY OF REGENERATION 



337 



of dry matter, on which depends, of course, the decrease of the 

 percentage of water observed during the subsequent stages. 



Experiment B. On July 13, another lot of 400 worms was oper- 

 ated on, of which 50 were immediately picked out at random and 

 weighed. (Compare table 2 and fig. 6.) The average weight of 

 the live worms was found to be 2.180 mgrm., and that of their 

 residue left after their complete dessication 0.576 mgrm., the per 

 cent of the water content being therefore, 73.58. The next deter- 



TABLE 2 



mination was made on 50 worms of the same lot five days after 

 the operation. The average weight of a live worm was at this 

 time only 1.920 mgrm., or 11.9 per cent less than in the first 

 or control group. The dry substance suffered a loss of 21.8 per 

 cent, whereas the quantity of water decreased only 8.3 per cent, 

 the result being that the per cent of water increased with remark- 

 able rapidity to 76.56. Ten days after the operation the per cent 

 of water in the regenerating worms had already reached the maxi- 

 mum, 77.71; fifteen days after the operation it had diminished to 

 77.52, and at later stages fell off more rapidly, being 76.92 twenty 

 days after the operation, and 75.17 thirty-nine days after that 

 event, when the regenerative rate had already been reduced to the 

 lowest limit. The data concerning this experiment are given in 



