Bull. U. S. B. F., 1909. Platk XXXVII. 
Fig. i. — R ight toothed forceps and cheliped 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 1 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 l. ser), carpal groove of upper lock hinge {u h groove), absorption area of fourth 
segment {Abs. a), breaking plane (at x), reversed basal hinges, or inner ball {h ball), and outer cup ( h socket)-, ten- 
dons {l.jl 1 and t. ex 1) of first joint, podobranchia ( pbr ), gill separator (ep), and proximal spur ( ps ) of claw. 
Figs. 3 and 4. — Base of great cheliped from below, disarticulated at second joint to show interlocking mechanism 
or spines (j 1 , and j 3 ) of first and third podomeres. 
