REPORT OF COMMISSIONERS OF INLAND FISHERIES. 307 



of regeneration under conditions differing in regard to the degree 

 of injury, molting, etc. But at this stage of the investigation it 

 may be of vakie briefly to discuss the general nature and significance 

 of the results derived from the present experiments, as a preliminary 

 to further study. 



1. The object of the present series of experiments was to as- 

 certain whether there was any regulation or interaction existing 

 between the processes of regeneration and molting. The results have 

 demonstrated that there is an interaction of such a nature between 

 these two processes that the introduction of the one, regeneration, 

 into the organism will disturb the normal activity of the other, 

 the molting process. Further, it maybe seen, also, that the funda- 

 mental fact underlying the present results is, that the rate of the 

 cellular activities involved in the molting process is retarded by the 

 cellular activities concerned in the process of regeneration. 



2. The character of the relations between regeneration and the 

 molting process, as studied so far, suggests an explanation of the 

 interaction on the basis of a variation in the distribution of available 

 energy. 



If we analyze the cellular activities involved in the two processes 

 of regeneration and molting it is evident that, although the process 

 of regeneration differs in one respect from that of molting, inasmuch 

 as regeneration involves the origin, development, and differentiation 

 of new tissues, while the molting process consists only in a develop- 

 ment and increase in the amount of tissue and the secretion of a new 

 shell, yet both regenerative and molting process alike involve the 

 multiplication and development of new cells from old cells already 

 present in the organism. Now it is a fundamental fact in physiology 

 that one of the essential conditions determining the rate of cell 

 multiplication and development is the amount of energy of the food 

 material assimilated by these cells. Therefore, since the process of 

 regeneration has reduced the rate of molting, it would seem most 

 natural to explain this result by the assumption that the regenerating 



