292 MORGAN. [VOL. I. 



The eyes were present and uninjured in all the individuals. 

 The antennae and antennules were also present. In some cases 

 the ends of the antennae were broken off. The third maxilli- 

 peds were present and uninjured. One of the chelae was 

 absent or regenerating in five individuals, and one of these 

 had lost both right and left chelae (6 per cent). A second leg 

 was absent in one case (i per cent), and a third leg in two 

 cases (2 per cent). In all, therefore, 9 per cent had lost one of 

 these legs. In not a single case were the fourth or fifth legs 

 missing or injured. 



In the abdominal region the third abdominal appendage 

 (belonging to the fourth segment) was absent in one female, 

 and in one male the second abdominal appendage (belonging to 

 the third segment) was absent. In another male the broken 

 proximal end of the second abdominal appendage was present, 

 and in another the first abdominal appendage was reduced in 

 size, and the second also was smaller than the normal, but the 

 third appendage (representing the fifth segment) was normal. 

 The two cases --one male, the other female-- where an 

 appendage was absent may be the result of individual variation ; 

 although it is also possible that the appendage was accidentally 

 pulled off in removing the crab from the shell. In the latter 

 case some evidence of tearing or breaking ought to appear, but 

 no such evidence was found. The individual in which the first 

 and second abdominal appendages are smaller than normal may 

 be the result either of variation or of incomplete regeneration. 

 The evidence, therefore, furnished by an examination of the 

 abdominal appendages is conflicting, and it is possible that the 

 appendages may be occasionally lost. 



The sixth abdominal appendages were present in all cases. 



Forty of the individuals were females and sixty males. 



Summary. - - The results, taken as a whole, show that the 

 first three walking legs are most often lost. The last two 

 thoracic legs were not absent in a single case examined, and 

 the same statement holds for the last abdominal appendages. 

 The second ($) and third (9) abdominal appendages were absent 

 in one case each, but whether from individual variation or from 

 loss during life is not known. Yet, since in one case small 



