370 THE GENUS PANOPEUS — BENEDICT AND RATHBUN. 



External lobes of the frout i^roduced and prominent. Median lobes 

 divided by a V-sbaped notch, and produced but very little beyond the 

 lateral lobes. Edge of the front thickened and granulate; granules 

 rather large. 



Coalesced tooth very wide, with nearly straight margin. Direction 

 of the margin almost transverse; angle of the orbit very little produced. 

 Third tooth a wide lobe, corners slightly rounded, the edge taking a 

 direction nearly x)erpendicular to the coalesced tooth. Second tooth 

 similar; direction of the margin intermediate between those of the first 

 and third. Posterior tooth pointed; anterior edge very short and 

 nearl}' perpendicular to the median line, posterior margin continuous 

 with the posterolateral margin of the carapace. 



Subhepatic region very coarsely granulate, the granules extending 

 up on the lower orbit. Tubercle prominent and spreading. Inner 

 lower angle of the orbit triangular, much produced, and separated from 

 the outer lobe by a wide deep sinus. External hiatus wide and rounded 

 at the bottom. 



Seventh segment of male sternum slightly exposed in some speci- 

 mens. Outline of proximal end of anchylosed segment angular. Ter- 

 minal segment rounded. 



Carpus of the chelipeds broad, smooth to the eye, but showing fine 

 granules under the lens. There is a very depressed spine at the inner 

 angle, and no carpal groove. Hands large, thin, deep, pitted, and 

 microscopically granulate. Dactyl slender, curved, in the large hand 

 having a small cylindrical basal tooth. Tubercle sometimes present on 

 the manus, near the articulation with the dactyl. Immovable finger 

 triangular, color running up on the palm and behind the gape, much as 

 in depressus. Fingers hooked at the tips. 



Length of carapace in large specimen, 10.5 millimetres; width, 26.5 

 millimetres. 



The specimens examined are from the Bay of Panama, F. H. Brad- 

 ley (Yale Univ. Mus.). 



14. Panopeus planissimus Stirnpson. 



(Plate XXI, tig. 5 ; plate xxiv, tigs. 1 and 2.) 



Xantho planissima. \V. Stimpson, Ann. Lye. Nat. Hist. N. Y., vii, p. 205, 1860. 

 Panopeus planissimus. W. Stiinpi-on, Ann. Lye. Nat. Hist. N. Y., x, p. 108, 187L 

 Eurypanoptus planissimus. A. Milne Edwards, Miss. Sci. au Mexique, pt. 5, i, p. 3'22, 

 1880. 



Carapace fiat; posterior two-thirds smooth and glabrous ; anterior 

 finely granulate and slightly rugose. 



Median lobes of front separated by a V-shaped notch, produced and 

 somewhat rounded. Lateral lobes little produced, rounded. Edge 

 of front thick and finely granulate, in some of the smaller dried speci- 

 mens apjiearing double. 



Coalesced tooth broadly emarginate ; at the inner angle of the orbit 



