BuLiv. U. S. B. F., 1909. 



Platk XXXVII. 

 spur 



■frt^) 



Fig. 4. 



Fig. I. — Right toothed forceps and cheUped of female lobster from lower side, showing periodic teeth, carpal ridge of 

 lower lock hinge, represented as if seen through hinge-process (/ h p), breaking joint (x), and interlock (s i and 

 s 3) between first and third podomeres. This claw is locked when closed by means of the underlapping lock 

 spine {lock sp) and underlapping tip of dactyl, indicated by arrow. 



Fig. 2. — Left cracker claw and cheliped of female from above, showing crushing tubercles, serial displaced teeth 

 on margin of "hand" {up. ser and I. ser), carpal groove of upper lock hinge (w k groove), absorption area of fourth 

 segment (Abs. a), breaking plane (at x), reversed basal hinges, or inner ball (A ball), and outer cup{/; socket); ten- 

 dons {t.Jl I and (. ex 1) of first joint, podobranchia ipbr), gill separator {e'p), and proximal spur {ps) of claw. 



Figs. 3 and 4. — Base of great chehped from below, disarticulated at second joint to show interlocking mechanism 

 or spines {s^, and ^) of first and third podomeres. 



