THE CANCROID CRABS OF AMERICA 239 



E2. More massive than the preceding, carapace deeply lobulate 

 anteriorly, antero-lateral margin with three large teeth 



behind the orbit lobopilumnus. p. 525. 



D^. Fronto-orbital border much more than two-thirds the greatest 

 width of carapace. 

 E'. Antennae not excluded from orbit. Chelipeds long, merus 

 reaching far beyond carapace. Carapace resembling a 



Portunid Melybia, p. 561. 



E^. Antennae excluded from orbit. 

 F'. Carapace rough above. 



G'. Merus of outer maxillipeds as long as or nearly 

 as long as broad. 

 Hi. Width of front between antennae more than 

 one-fourth width of carapace. Regions dis- 

 tinct. Fingers pointed Eriphia, p. 545. 



H2. Width of front between antennae less than 

 one-fourth width of carapace. Antennae 

 remote from orbit. Regions indistinct. Fin- 

 gers of minor chela spooned-Eriphides, p. 552. 

 G'^. Merus of outer maxillipeds twice as broad as long. 

 Carapace and chelipeds armed with black spines. 



Domecia, p. 553. 

 F2. Carapace smooth above. 



G'. Chelipeds with short arms, projecting but little 

 outside the carapace. Front lobed or dentate. 



Trapezia, p. 556. 

 G^. Chelipeds with long arms, projecting far outside 

 the carapace. Front acutely spinate. 



Quadrella, p. 560. 

 B2. Eyestalks long and flat; when in orbits their acute anterior edge is con- 

 tinuous with margin of carapace. Merus of outer maxilliped trans- 

 versely oblong, inner margin arcuate, without indentation. Carapace, 

 chelipeds and legs fringed with long hair Acidops, p. 533. 



Genus CARPILIUS Leach 



Carpilius Leach, in Desmarest, Diet. Sci. Nat., vol. 28, 1823, p. 228; type, C. 

 maculalus = Cancer maculaius Linnaeus, 1758. 



Carapace broad, very convex in both directions, smooth (except 

 for some coarse pitting inside frohtal and antero-lateral borders), 

 with no indication of regions; antero-lateral borders strongly arched, 

 thick, entire, smoothl}^ molded; postero-lateral borders strongly 

 convergent, straight, with a prominent tubercle at angle of junction 

 with antero-lateral. Front moderately broad (less than a third the 

 greatest width of carapace), deflexed, three-lobed, the middle lobe 

 prominent, the edges of all thickened. Orbital margins entire, the 

 upper margin thickened and forming a well-marked blunt tooth at 

 its junction with the antero-lateral margin. Eyes on short, thick 

 stalks. Antennules folding obliquely; inter-antennular septum broad. 

 Basal article of antenna long, flat, running up into an oblique cleft 

 between margin of front and infra-orbital plate; flagellum very small, 

 less than half diameter of orbit and lodged in said cleft. Merus of 



