264 REPORT OF COMMISSIONERS OF INLAND FISHERIES. 



The Effect of Regeneration upon the Length of the 

 Period Between Molts. 



a. Ezperiments. 



The first question in regard to the relation between the processes 

 of regeneration and molting is whether, in the lobster, the process 

 of regenerating an appendage really has any influence upon the 

 length of the molting period. This may be answered by comparing 

 the length of the molting process in a group of normal lobsters with 

 the length of the corresponding process in a group of regenerating 

 lobsters. 



For this purpose, on July 8, 1905, 80 fourth stage lobsters were 

 taken from one of the hatching pools. The specimens were selected 

 out of several hundreds which had molted into the fourth stage 

 during the night of July 7. They were all approximately of the 

 same size and in normal condition. 



These 80 selected specimens were then separated into three groups 

 which may be designated as series A, A^, and A4.* The number 

 of individuals in each group was as follows: Series A, 30; series A^, 

 25; series A4, 25. The lobsters in series A were kept in a normal 

 condition; the 50 specimens in series A^ and A4 were all mutilated 

 by the removal of both chelipeds. The difference between series Aj 

 and A4 consists in the time of mutilation. As the result of previous 

 observations there were reasons to suspect that an injury occurring 

 immediately after a molt might not perceptibly affect the length 

 of the molting process. Accordingly, in order fairly to test the 

 influence of regeneration, 25 of the lobsters were mutilated July 9, 

 one day after molting to the fourth stage (series A^); and the other 

 25 specimens were mutilated July 12, four days after molting to the 

 fourth stage (series A4). 



*The sub-numerals indicates the number of days intervening between the time of mutila- 

 tion and the preceding molt, as will be described. 



