THE GRAPSOID CRABS OF AMERICA. 181 



filled by antennae; antennules transverse. Buccal area very convex. 

 Outer maxillipeds large, longitudinally placed, ischium of good size 

 and distinct from the elongate merus, joints of palpus large, end 

 to end. Chelipeds stout, smooth. Legs similar, second longest. 

 Sternum flat, forming an acute angle with the plane of the carapace. 

 Abdomen of male triangular, 7-segmented, although fifth and sixth 

 segments are partially fused; abdomen of female suborbicular, sev- 

 enth segment invaginated in the sixth. 

 Contains only one species. 



PINNOTHERELIA LAEVIGATA Milne Edwards and Lucas. 



Plate 39, figs. 1-3 ; plate 40, figs. 1 and 2. 



Cyclograpsus (?) gnatherion KINAHAN, Journ. Roy. Dublin Soc., vol. 1, 1857, 



p. 343 (type-localities, Chinchas Islands and Callao; types in Mus. 



Roy. Dublin Soc.). 

 Pinnotherelia laevigata MILNE EDWARDS and LUCAS, in d'Orbigny's Voy. 



I'Amgr. M6rid., vol. 6, pt. 1, 1843, p. 25 (type-locality, Chile; type in 



Paris Mus.). 

 Pinnotherelia loevigata MILNE EDWARDS and LUCAS, in d'Orbigny's Voy. 



FAm6r. M6rid., vol. 9 (atlas), 1847, pi. 11, figs. 1-le. 



Diagnosis. Carapace transversely oblong. Eyes far apart. Palp 

 of outer maxilliped with all three joints large, end to end. Sternum 

 flat, forming an acute angle with dorsal plane. Chelipeds heavy. 

 Second leg longest. 



Description. Carapace subquadrilateral with the corners rounded 

 off, a little wider at anterior than at posterior angles; hard and 

 smooth, a longitudinal groove each side of the cardiac region, a 

 shallow groove behind the gastric region ; flat except in its anterior 

 portion, which is strongly bent down; front two-fifths as wide as 

 carapace, slightly arcuate in dorsal view, true edge seen only in front 

 view, and transverse except at middle; posterior margin bent down, 

 concave; lateral margin acute. Chelipeds and legs smooth without 

 teeth or roughness of any kind. Outer surface of wrist rounded, 

 palm inflated, upper and lower margins convex, distal margin very 

 oblique: fingers similar, narrowly gaping, tips pointed, thumb 

 shorter, horizontal. Legs thick, flattened, margins of merus subpar- 

 allel, merus and propodus thickly hairy below, dactyli moderately 

 curved; second leg longest, first next, then third and fourth. 



Measurements. Male (2435) length of 'carapace 10.7, width of 

 same 12.7 mm. 



Habitat. Cast shells were found at Callao on rocks of inner side 

 of natural dyke of rubble separating lagoon at mouth of river from 

 ocean. 



Range. Peru and Chile; Porto Arenas, Patagonian Canal 

 (Cano) ; Marquesas Island, south mid-Pacific Ocean. 



