REPORT OF COMMISSIONERS OF INLAND FISHERIES. 121 



made primarily for the purpose of comparing the power of regenera- 

 tion at different levels of the appendages, but one of the results was 

 so unusual that it may be fittingly described here. In one of the 

 lobsters the normal second left leg, the propodite had been cut off 

 at a level just above the second distal joint. The structure which 

 regenerated at this cut was the very small claw shown in Figure 23. 

 This rather remarkable structure was very rudimentary and no 

 evidence of its being functional was observed. 



With the exception of this last case the artificial mutilations thus 

 far attempted, therefore, have not given any very promising results, 

 but still this is no ground for discontinuing such experiments. They 

 only show that we have not yet discovered just where we may insert 

 an obstacle between the cogwheels, if the figure is permitted, which 

 will cause the growing machine to duplicate its products. 



3. The Regeneration of Two Crusher Claws. 



As far as I am aware the following two specimens are the only 

 authentic cases on record in which a lobster has developed a crushing 

 chela on each side of the body through the process of regeneration. 

 Accordingly, a somewhat detailed description of these specimens 

 will be given. 



a. Data. 



Specimen No. 8. Figs. 24-31. 



This lobster is the same animal which regenerated the triple claw 

 on the walking leg described on page 113. It will be recalled that 

 it had been recently taken from the trap, was a female, and meas- 

 ured 8 3-16 inches in length. On July 26, 1905, both chelee and 

 the second and third right walking legs were autotomously removed 

 by pinching the tip of the limb with a forceps. On September 28, 

 sixty-four days after the amputation, the lobster moulted and then 

 measured 8^ inches. It had, meantime, regenerated both chelae, 

 and the second and third right thoracic legs. 



