314 BULLETIN 97, UNITED STATES NATIONAL MUSEUM. 



those of median pair only a little wider than those of lateral pair; 

 lobes prominent, as if arising from lower margin of front, armed 

 with rather acute granules; deflexed part of front concave and 

 granulous. Anterior part of carapace granulate; granules elongate, 

 sub-squamifoim, consisting of a linear series of two to five small 

 granules, bearing now and then minute setae, visible only with a lens 

 in the adult. Posterior part of carapace, except of branchial region, 

 without granules but appearing punctate; in the young the punctae 

 are beset with hair. Small transverse folds cross the posterior part 

 of the branchial region. 



General aspect of carapace rather fiat, only feebly convex ante- 

 riorly. Mesogastric sulcus narrow, but reaching front; on each side 

 a short sulcus runs at right angles toward the supero-internal angle 

 of the orbit. Gastro-carcliac sulcus deep. 



Chelipeds rather slender. Merus outwardly rugose, its upper 

 angle acute and denticulate; lower angle also conspicuously denticu- 

 late ; infero-inner angle dilated toward the apex and bearing a rather 

 large tooth or denticulate projection. Carpus coarsely granulous, 

 without inner tooth or prominence. Hand rather swollen, covered 

 outside with rather large granules; granules of inner surface much 

 depressed and less crowded ; no trace of an inner crest ; upper margin 

 limited by a denticulate crest. Palm shorter than fingers ; the latter 

 are slightly dentate, leave a small gape when closed, the apices horny 

 and slightly excavate. 



Legs long and slender; penult pair notably longer than the others. 

 Merus from two and one-half to three times as long as its width, 

 the propodus one and one-half times as long as the dactylus. All 

 the articles bear a small, denticulate crest above and are freely 

 squamose on the posterior surface; the merus has at its extremity a 

 stout, acute tooth directed forward. Dactylus and distal end of 

 propodus bear a few short setae. (After Nobili.) 



Measurements. — Male cotype, length of carapace 7, width of same 

 at second ambulatory legs 8J, width between exorbital angles 8, 

 width of front 4.5 mm. 



Range. — Colombia (Pacific coast) and Ecuador. 



SESARMA (HOLOMETOPUS) ANGUSTUM Smith, 



Plate 92. 



Sesarmn anguHia Smith, Trans. Connecticut Acad. Arts and Sci., vol. 2, 

 1870, p. 159 (typo-locality, Pearl Islands, Bay of Panama; male holo- 

 type, Cat. No. 659, P.M.Y.U.). 



Diagnosis. — Longer than wide. Chelipeds small. Merus joints of 

 legs diminishing slightly from middle to distal end. 



