No. 6.] 



LIABILITY TO INJURY. 



289 



I. DESCRIPTION OF THE APPENDAGES. 



The eyes, antennae, antennules, and mouth parts (maxillae 

 and maxillipeds) are not sufficiently different from those of other 

 Decapoda to call for special comment. The first three pairs of 

 walking legs are large and strong (Fig. i), and protrude from 

 the shell when the animal moves about. 



11 



FIG. 8. First abdominal appendage of female (belonging to second segment). FIG. 9. Second 

 abdominal appendage of female. FIG. 10. Third abdominal appendage of female. 

 FIG. n. Fourth abdominal appendage of female (= third abdominal appendage of male). 

 (Same scale as last figures.) 



The fourth (Fig. 2) and fifth (Fig. 3) pairs of legs are small 

 and weak. They are brought to the edge of the shell when the 

 crab is active, but take no part in locomotion. They may be 

 of service in bracing the animal against the shell. 



The anterior abdominal appendages are entirely absent on 

 one side of the body, --the side toward the axis of the shell. 

 Those on the other side are said to represent in the female the 

 second, third, fourth, fifth, and sixth appendages (Figs. 8, 9, 



