276 STALK-EYED CRUSTACEA 



Section i. Grapsini. 



No ridge on tlie third and fourth joint of external 

 maxillipedes. 



Section 2. Sesarmini. 



A ridge on the third and fourth joint of external 

 maxilHpedes. 



Section i. Grapsini. 



Grapsini .... Miers, Kingsley. 

 Grapsincc .... Dana. 



No ridge on the third and fourth joint of external 

 maxillipedes. 



Synopsis of the Genera. 



A. There is a rhomboidal space between external 

 maxillipedes. 



a. External antennae excluded from the orbit. 



I. The fourth joint of external maxillipedes as long as 

 the third joint. — {Goiiiopsis.) 



b. External antenna: not excluded ^y=c:r^-^::^>-^^ 

 from the orbit. /''x 



a^. Front less than half the width of [ - — - 



the carapace. Vczi 



a-. One tooth behind orbital angle. "^^^ 



2. Fingers of first pair of legs ex- 

 cavated. — {Grapsns.) 



3. Fingers sharp pointed. — {Geogi-apsus.) 



//-. Two teeth behind the orbital angle. — {I^eptograpsus.) 

 b^. Front more than half the width of the carapace. 

 5. Carapace transverse. — {Pachygrapsus.) 



