Plate 13. Second-Stage Lobster. 



Figure 19. Bight cheliped from behind, M=22. The functional exopodite 

 is still attached to the basipodite, but the endopodile is relatively larger and 

 stronger than in the first stage. The end of the propodite nearly equals in length 

 the opposing dactylopodite. The claw itself is better formed than in the first 

 stage, although in the second it is hardly more functional. The podobranch and 

 epipodite are attached to the coxopodite. In this stage is shown the beginning of 

 the torsion of the claw, of which the dactyl in the first stage opened vertically 

 upward and somewhat outward. For further references see Herrick,* and Emmel.f 



*F. H. Herrick, Biol. Bull.. 1905, IX. 130-137. 



t V. E. Emmel, Journal of Exper. Zool. 1906, IV. 603-618. In this paper Emmel shows the 

 interesting parallel between the torsion in the development of the chela through the stages , 

 and the torsion in the development of the claw during regeneration. 



