THE KING CRAB 



>^/ 



C3.m. 



Pm^^^ 



Fig, 212. — Diagram of the ventral surface of the same King- 

 Crab, showing the six legs, the genital oiDerculum {Op) 

 and the branchial plates (Br. app.). Sfr, sub-frontal 

 piece ; Cam, upper lip or camerostome ; M, mouth ; 

 Pmst, anterior sternal plate ; Chi, the chilaria, which are 

 the same parts as are seen in the pentagonal sternum of 

 the Scorpion (Fig. 206, met) and in the oval plate of 

 Pterygotus (Fig. 207, m). 



28: 



