3Q2 CRUSTACEA. 



m&risferme ac in cinereo, lateribus vix excavatis, segmento postico parce 

 dblongo, apice late rotundato. Sternum pone aream buccalem nudum. 



Carapax not areolate, anteriorly somewhat granulous. Orbit incom- 

 plete below. Third joint of outer maxillipeds very slightly oblong, 

 much shorter than second, naked excepting crest, which is quite 

 slender, and crosses only the antero-external angle of the second 

 joint; second joint naked. Fifth joint of second feet not tomentose 

 at apex, tarsus with lines which are rather lax tomentose, not at 

 all spinulous. Hand smooth and shining, fingers of male not denti- 

 culate within. Male abdomen nearly as in the cinereus, sides very 

 slightly excavate, last segment very little oblong, apex broadly 

 rounded. Sternum immediately behind the mouth naked. 



Plate 23, fig. 4 a, male, enlarged two diameters ; b, outer maxillipeds, 

 enlarged five and a half diameters ; c, male abdomen, enlarged four 

 diameters ; d, hand, enlarged four diameters ; e, tarsus of fourth pair, 

 enlarged. 



Island of Maui, Hawaiian Group, Pacific. 



Length of carapax of male, 3-7 lines; breadth, 4'6 lines; ratio, 

 1 : 1-24. Sides rather regularly arcuate. Fingers somewhat gaping, 

 and remarkable for being entire within instead of denticulate. There 

 are some faint traces of areolation. 



C. granulatus, DANA, Proc. Acad. Nat. Sci. Philad., 1851, v. 251. 



GENUS CHASMAGNATHUS, DC ffaan. 



The genus Chasmagnathus is between Helice and Hemigrapsus in 

 its characters. It has the narrow and curvately declivous front, thick 

 body, and outer maxillipeds of Helice, but with arcuate sides emar- 

 ginated anteriorly, and short eyes, as in Hemigrapsus. Like Helice, 

 moreover, the fourth joint of the outer maxillipeds is articulated with 

 the third joint, nearer its outer apex than in most of the Grapsidae, 

 though nearly as in Qoniograpsus cruentatus. The third joint of the 

 outer maxillipeds may be even longer than the second, and is dilated 



