42 BULLETIN 152, UNITED STATES NATIONAL MUSEUM 



Merus of cheliped extending far beyond the carapace, armed with 

 three spines on the inner margm. A strong spine at inner angle of 

 carpus, a smaller spine near distal end of outer margin. Seven 

 carinae on manus, a spine on outer surface at articulation with 

 carpus, another spine at distal end of upper margin. First three 

 pairs of legs fiat, lamellate. Swimming legs unarmed. 



Penult segment of male abdomen suboblong; terminal segment 

 small, somewhat invaginated in the preceding. 



Color. — Mottled olive green or purplish and variegated yellow- 

 brown with white patches corresponding to their environment of 

 gulf-weed encrusted with white colonies of bryozoa. 



Measurements. — Male (13883), total length of carapace 29, total 

 width 55.6, width at anterior base of lateral spine 47.7, fronto-orbital 

 width 20.4, width of front between tips of inner orbital teeth 11.2 mm. 

 Female (2368), total length of carapace 37.1, width of same 76.1, 

 width at anterior base of lateral spine 62.7, fronto-orbital width 30, 

 width of front between tips of inner orbital teeth 14.4 mm. 



Habitat. — Normally in masses of floating gulf-weed in mid-ocean 

 and especially along the Gulf Stream. 



Range. — North Atlantic Ocean from Nova Scotia (43° N. lat.) 

 south via Gulf of Mexico to Guiana; Brazil (Gerstaecker). Mid- 

 Atlantic; Bermuda. Kerguelen Island, South Indian Ocean. 



Material examined. — See table, pages 38-41. 



PORTUNUS (PORTUNUS) ANCEPS (Saussure) 



Plate 15 



Lupea anceps Saussure, M6m. Soc. Phj's. Hist. Nat. Geneve, vol. 14, 1858, p. 



434 [18], pi. 2, fig. 11-116 (type-locality, Cuba; type in Geneva Mus.). 

 Neptunus anceps A. Milne Edwards, Arch. Mus. Hist. Nat., Paris, vol. 10, 



1861, p. 328 (not Lupa bsllicosa Stimpson); Crust. R6g. Mex., 1879, p. 213. 

 Lupea duchassagni Desbonne, in Desbonne and Schramm, Crust. Guadeloupe, 



1867, p. 39, pi. 4, fig. 25 (type-locality. Guadeloupe; cotype (?) in Geneva 



Mus.). 

 Achelous anceps Stimpson, Ann. Lye. Nat. Hist. New York^ vol. 10, 1871, p 



113 [23].— Verrill, Amer. Journ. Sci., vol. 25, 1908, p. 378, text-fig 26 



pi. 20, figs. 1 and 2; pi. 27, fig. 4 (not Neptunus ventralis A. Milne Edwards) 

 Neptunus sulcatus A. Milne Edwards, Crust. Reg. Mex., 1879, p. 216, pi. 39 



fig. 3-3c (type-localities, Guadeloupe and 11° 49' S. lat., 37° 27' W. long. 



17 fathoms; cotype from latter locality in M.C.Z.). 

 Portunus ventralis Rathbun, Bull. U. S. Fish Coinm. for 1900, vol. 2, 1901, 



p. 45 (not Neptunus ventralis A. Milne Edwards). 

 Portunus (Achelous) anceps Rathbun, in Boeke, Rapport Visscherij Kolonie 



Curacao, pt. 2, 1920, p. 17 (not Amer. Nat., vol. 34, 1900, p. 14). 



Diagnosis. — A spine at extremity of outer margin of arm. Sub- 

 distal spine of palm at distal fifth of upper margin. Median pair of 

 frontal teeth very small. 



