472 BULLETIN 152, UNITED STATES NATIONAL MUSEUM 



Genus MENIPPE de Haan 



Menippe db Haan, Fauna Japon., Crust., 1833, pp. 4 and 21; type, M. rumphii 

 (Fabricius) . 



Carapace broad, transversely oval, moderately convex fore and aft, 

 very slightly so from side to side; regions, except gastric, little de- 

 fined. Several pits form a semicircle on either side opposite the last 

 two lateral teeth. Antero-lateral borders long, strongly arched, cut 

 into four teeth besides orbital; postero-lateral borders slightly 

 shorter than antero-lateral, convergent; posterior border short. 

 Front narrow, about a fifth or less than a fifth the greatest breadth 

 of carapace, rather prominent, almost horizontal, cut into two lobes, 

 the outer angle of each of which forms a distinct tooth or lobule. 

 Orbit with three grooves near the outer angle well marked; inner 

 orbital angles, both upper and lower, pronounced. Eyes on short, 

 thick stalks. Side edges of front not turned down; the short basal 

 antennal article does not nearly reach the front, so that the cavities 

 of orbits and antennules are not properly separated; next antennal 

 article just reaches front, and the long antennary flagellum stands in 

 the orbital hiatus. Antennules fold nearly transversely. Anterior 

 edge of merus of external maxillipeds oblique and a little sinuous but 

 not excised. Ridges of endostome complete, but low and faint. 

 Chelipeds massive, a little unequal in both sexes; fingers stout, 

 pointed, not hollowed. Abdomen of male singularly broad, all seven 

 segments distinct. 



Indo-Pacific region; both coasts of middle America. 



KEY TO THE AMERICAN SPEOES OF THE GENUS MENIPPE 



A'. Surface of carapace not nodose, almost smooth. Antero-lateral teeth or 

 lobes shallow or little projecting. A stridulating apparatus present. 

 B^ Margin of front with two lobules on outer side of each submedian lobe. 

 C. Second antero-lateral lobe not bilobate. Two lobes or teeth on lower 



orbital margin mercenaria, p. 472. 



C^. Second antero-lateral lobe bilobate. Three lobes on lower orbital 



margin frontalis, p. 477. 



B*. Margin of front with one lobule on outer side of each submedian lobe. 



Second antero-lateral lobe bilobate obtusa, p. 478. 



A^. Surface of carapace anteriorly nodose. Antero-lateral teeth strong, project- 

 ing well out from carapace. No stridulating apparatus. .nodifrons, p. 479. 



ANALOGOUS SPECIES ON OPPOSITE SIDES OF THE CONTINENT 



Atlantic Pacific 



mercenaria frontalis 



MENIPPE MERCENARIA (Say) 



STONE CRAB 



Plates 191-193 



Cancer mercenaria Say, Journ. Acad. Nat. Sci. Philadelphia, vol. 1, 1818, p. 448 



(type-locality, "the southern states"; type, 114.3 mm. wide, not extant). 

 Xantho mercenaria Milne Edwards, Hist. Nat. Crust., vol. 1, 1834, p. 399. 



