366 CRUSTACEA. 



Length of carapax of a male, eleven and a half lines; breadth, 

 fourteen lines ; length of front between the eyes, six lines ; height of 

 hand, six and a half lines. The carapax has a transverse depression 

 but no distinct areolets, excepting the cardiac, which is nearly hex- 

 agonal. The third joint of the outer maxillipeds is about as long as 

 the second, the second has its surface partly naked. There is an ob- 

 lique raised line on the postero-lateral region, but it is hardly distinct. 

 There are no indications of a third emargination on the lateral margin, 

 like that of the granulatus. The surface of the sternum between the 

 buccal area and the apex of the abdomen is naked, excepting very 

 near this area. 



C, Icevis, PANA, Proc. Acad. Nat, Sci. Philad., 1851, v. 252, 



GENUS HELICE, De Haan. 



Carapax siibguadratm, angulisanticisacutis,fronte paulo Ireviore quam 

 latitudinis dimidium carapacis, septoque inter-antennali media connatis. 

 Oculi tertio latitudinis carapacis breviores. Articuli maxillipedis 

 externi 2dus Ztiusque obliqud canaliculati, Stio paulo oblongo non bre- 

 viore quam 2dus, apice latiore. Pedes maris antici sat breves. 



Carapax nearly quadrate, anterior angles acute, front somewhat 

 shorter than half the breadth of the carapax, and coalescing with the 

 inter-antennary septum below. Eyes shorter than one-third the 

 breadth of the carapax. Second and third joints of outer maxil- 

 lipeds with an oblique longitudinal channel, the third joint a little 

 oblong, not shorter than second, at apex broadest. Anterior feet 

 of male rather short. 



This genus differs from Sesarma and other Grapsidse in its narrow 

 male abdomen. It has a broader front and shorter eyes than Cleisto- 

 stoma, and this front unites below with the septum, between the inner 

 antennae. 



The fossettes of the inner antenna) extend laterally as far as the 

 front, so that the outer antennas stand just outside the outer angle 

 of the front, The basal joint of these antennae is very broad and 



