198 PROCEEDINGS OF THE ACADEMY OF [1880. 



short. AnteniiiB entering the oi'bit. Male abdomen seven- 

 jointed, the second joint verj^ short. 



* 



C. angulatas Dana. 



Cyrtograpsus angulatus Dana, Proc. Acad. Nat. Sci. Phila., 1851, p. • 



250. U. S. Expl. Exped., p. 352, PI. 22, f. 6 (1852). 

 Cryptograpsus angulatus Smith, Trans. Conn. Acad., ii, p. 37, 1869. 



Carapax uneven, granulate. Sides three-toothed, second tooth 

 small. Orbits with a slight fissure above. Feet all granulate. 

 Hands inflated; fingers acuminate. 



Rio Negro, Patagonia! (U. S. Expl. Exped.). 



C. cirripes Kingsley ex Smith. 



Cryptograpsus cirripes Smith, Trans. Conn. Acad, ii, p. 11, PI. I, f. 3 

 (1869). . 



Carapax depressed, areolate ; front narrow, slightly excavate. 

 Sides of carapax strongl}'^ arcuate, with four teeth behind the angle 

 of the orbit, the second and last teeth much smaller than the 

 others ; all of the borders of the carapax are crenulate. Chelipeds 

 stout, granular. Propodal joints of first, second, and fourth, and 

 dactylus and carpus of fourth pair of ambulatory feet haired. 



Bio Janeiro! (Captain Harrington, Peabody Academy of Science, 

 Salem, Mass., types). 



Genus PACHYGRAPSUS Randall (1839); Stimpson (1858). 



Carapax somewhat narrowed behind, and with transverse striae-. 

 Front more than half the width of the carapax, sides entire, or 

 with one or two teeth ; inner sub-orbital lobe small, allowing the 

 antennae to enter the orbit. External maxillipeds widelj' gaping, 

 meros as broad as long. Type, P. crassipes. 



Synopsis of Species. 

 Sides entire. 



Front straight or nearly so. 

 Numerous transverse folds on carapax ; lower margin of hand spined. 



corrugat^ls. 

 Carapax but little plicate, hands smooth below. mthiopic^is. 



Front strongly sinuate. 

 Hands smooth. minutus. 



Hands externally with longitudinal ridges. j)^'^'^'^^'^^- 



Sides with one tooth behind the orbital angle. 

 Posterior distal angle of meros of fifth pair of feet rounded. 



Front with a prominent tooth at angle. crassipes. 



Front slightly sinuate without prominent teeth. maurtis. 



Posterior distal angle of meros of fifth feet dentate. 



