1880.] NATURAL SCIENCES OF PHILADELPHIA. 195 



longer than broad. Chelipeds much as in Metopograpsus onessor-, 

 the hand granulate above, fingers acuminate. Posterior distal 

 angle of meral joints of ambulator}^ feet rounded, entire or finely 

 serrate, there being a variation in the sides of the same specimen. 



West Indies ! (Dr. Wilson) ; Key West, Fla. ! (Dr. A. S. Packard, Jr., 

 Peab. Acad). 



0. longitarsis Kingslcy ex Dana. 



Grapsus longitavsis Dana, Proc. Acad. Nat. Sci., Phila., 1851, p. 249. 

 U. S. Expl. Exped. Crust., p. 339, PI. XXI, f. 4 (1852). 



Pmmiotu Archipelago (Dana). 



Genus GEOGEAPSTJS Stimpson, 1868 (Biscoplax, Am. Ed., 1867). 



Carapax depressed, sides curved in front, straight behind, one 

 tooth behind the angle of the orbit. Front narrow, strongly de- 

 flexed. Internal suborbital lobe large. Antennae entering the 

 orbit. Dactyli of chelipeds acuminate. 



Synopsis of Species. 



Meros of chelipeds with a laminiform expansion of the anterior margin. 

 Front nearly straight. 



Folds of carapax transverse. Udidus. 



Folds of carapax oblique. gvayi. 



Front arcuate. crinipes, 



Meros not expanded, carapax tuberculate anteriorly. longipes. 



G. lividus Stimpson ex Milne-Edwards. 



Orapsus lividus Edwards, Hist. Nat. Crust., ii, p. 85 (1837). 

 Grapsus brevipes Edw., Ann. Sci. Nat., Ill, xx, p. 170 (1853). 

 Geograpsus litidus Stimpson, Proc. Acad. Nat. Sci. Philadelphia, 



1858, p. 101. 

 Geograpsus occidentalis Stimpson, Annals N. Y. Lye, vii, p. 230 



(1860). 



Carapax much broader than long, depressed. Plications nearly 

 transverse. Frontal lobes prominent, front deflexed, its margin 

 nearly straight. Sides of carapax slightly arcuate. Orbit with a 

 deep fissure below. Meros of chelipeds above and below with 

 transverse rugae, its anterior margin expanded, proxiraall}^ den- 

 ticulate, distall}' the teeth are larger. Carpus granulate and with 

 a short spine on the inner margin. Hand and dactylus tubercu- 

 late above, externally and below with short, oblique rugae ; fingers 

 acuminate. Distal angle of meral joints of the last pair of ambu- 

 latory feet rounded. 



Isle Bartholomeio, W. I.! (A. Goes) ; Chili! (Guerin) ; West Indies 

 (Auct.) ; Cape St. Lucas (Stm.). 



