428 BULLETIN OP THE BUREAU OP FISHERIES. 



aa. Carapace narrower; a circle drawn as before will fall well outside the tips of the fifth, sixth, and 



seventh anterolateral spines (Subgenus Acheloiis). 



b. Interocular teeth eight, the inner orbital being bilobed spinimarms. 



bb. Interocular teeth six, the inner orbital being entire. 



c. Basalarticleof last pair of legs with an acute, upright spine sebcE. 



cc. Basal article of last pair of legs without an erect spine. 



d. Internal spine of carpus extending to middle of hand or beyond spinicarpus. 



dd. Internal spine of carpus of moderate length. 



e. Superoextemal surface of chela with a conspicuous, smooth silvery or iridescent area . .ordwayi. 

 ee. Superoextemal stirface of chela ridged and not iridescent. 

 /. Superior margin of hand with two distal spines, one behind the other; posterior lateral 



spine distinctly longer than the others anceps. 



ff. Superior margin of hand with only one distal spine; posterior lateral spine little if any 

 longer than one in front of it depressifrons. 



Portunus gibbesii (Stimpson). PI. xxxiii, fig. i. 



Lupa gibbesii Stimpson, 1862, p. 57. 



Acheloiis gibbesii Stirapson, 1862, p. 222; VerriU, 1908, p. 389. 



Portunus gibbesii Rathbun, 1900, p. 140. 



Carapace more than twice as wide as long, not tumid, thickly covered with small spherical granules, 

 pubescent, and with three or four naked, transverse ridges, two of which arise from the lateral spines and 

 run toward the gastric region ; frontal teeth 8, including the two points of the inner orbitals, each of which 

 is notched at the summit; the 2 median teeth are narrower and slightly more advanced than the next 

 pair; external orbital tooth not much larger than the teeth of the anterolateral border, which are stout, 

 acute, and directed forward ; the last tooth, or lateral spine, slender, very sharp, curved forward and about 

 as long as the space occupied by the four preceding teeth ; near the anterolateral margin at the base of 

 the teeth are one or more small, naked, iridescent areas. 



Chelipeds long, slender; meros with five or six spines in front and one at the distal end; carpus 

 with a large internal and a smaller external spine ; chela slender, ribbed on all its sxnfaces; the ribs con- 

 tinued onto the fingers and made rough by sharp-pointed , appressed tubercles ; there are two spines on 

 the hand, one at the articulation with the carpus, the otlier near the distal end of the superior rib ; fingers 

 nearly straight with inciu'ved tips. 



Length of a male, 29 mm.; width, 61 mm. 



Color, brownish red, the transverse ridges on the carapace and the spines and margins of the cheli- 

 peds carmine red. 



On the American coast the range of this crab extends as far north as Woods Hole , Mass. It is fairly 

 common about Beaufort and is often taken in the deeper channels of the harbor. 



Portunus sayi (Gibbes). PI. xxxm, fig. 2. 



Portunus pelagicus Bosc, 1805, p. 219. 



Lupa pelagica Say, 1817, p. 97; De Kay, 1844, p. n (not Z.. pelagica Leach). 



Lupa sayi Gibbes, 1850. p. 178. 



Neptunus sayi Stimpson, i860, p. 220. 



Portunus sayi Rathbun, 1897, p. 22; ibid, 1898, p. 276; Verrill, 1908, p. 376; Sumner, 1911, p. 672. 



Carapace very nearly twice as wide as long, somewhat tumid, smooth and polished to the naked eye, 

 but with a lens it is seen to be finely granulate ; frontal teeth 6, including the inner orbitals; the 2 median 

 teeth smaller but on a line with the next pair; external orbital tooth larger than those of the antero- 

 lateral border except the ninth, which is stout, acute, and about as long as the space occupied by the 

 three preceding teeth ; the teeth of the anterolateral border bltint and increasing slightly in size pos- 

 teriorly. 



Chelipeds of moderate length, somewhat larger in the male than in the female; meros with four, 

 rarely three, stout, curved spines in front, none behind ; carpus with two spines. Manus with an acute 

 spine at the articulation and a smaller one near the base of the movable finger ; the external sinf ace with 

 two longitudinal ribs of which the lowermost extends onto the finger; the superior siu^ace with three ribs 

 which are continued onto the finger, the innermost one being ciliate beneath. 



Length of a male, 20.5 mm. ; width, 40 mm. 



