STALK-EYED CRUSTACEA 279 



than in the water. The water there is not very salt, 

 especially in the wet season. 



2. Grapsus. 



Grapsiis . . . Lamarck, H. Milne Edwards, Miers, 

 Kingsley. 



Carapace depressed, with the cervical sutures strongly 

 defined; the lateral margins regularly bowed, and armed 

 with a single tooth behind the exterior orbital angle ; the 

 dorsal surface marked with transverse raised lines, which 

 are strongest on the branchial regions ; the front is of 

 moderate width, strongly deflexed, its anterior margin is 

 entire and slightly arcuated ; the orbits of moderate size, 

 rather deep, and their inferior margins have a fissure or 

 notch near the exterior orbital tooth. The eye-peduncles 

 are robust and short. The internal antennae are trans- 

 versely folded in very narrow fossets. The basal joint of 

 external antennae is very short, and is produced at its 

 antero-external angle ; it lies within the interior orbital 

 hiatus, between the front and the interior subocular lobe 

 of the orbit, which is dentiform and acute ; the flagellum 

 is short. The epistome is transverse and rather large ; 

 the buccal cavity small, and the ridges of the endostome 

 distinctly defined. The external maxillipedes are narrow ; 

 the fourth joint is truncated or slightly concave distally, 

 and it articulates with the fifth joint at its antero- 

 external angle. The first pair of legs robust and rather 

 short ; their fourth joint is triangular in section, with the 

 anterior margins toothed ; the fifth joint has a strong 

 tooth on the inner margin ; palm short, granulated 

 above ; fingers toothed on their inner margin, and ex- 

 cavated at their tips. Walking legs large and robust. 



