422 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 5 



Remarks. — This rarest of swimming crabs in the Galapagos Islands 

 may be distinguished from the two commoner species, P. (A.) stanfordi 

 Rathbun and P. (A.) angustus Rathbun, by the paired spine on the poste- 

 rior margin of the carapace, although it may be incipient in young speci- 

 mens. 



P. (A.) tuberculatus is now recorded from the Galapagos Islands. Its 

 vertical range has been increased to 70 fms. 



Genus CRONIUS Stimpson, 1860 



Cronius ruber (Lamarck) 



Plate 72, Figs. 3, 4 



Portunus ruber Lamarck, Hist. Nat. Anim. sans Vert., vol. 5, p. 260, 



1818. 

 Cronius ruber Stimpson, Ann. Lye. Nat. Hist. New York, vol. 7, p. 225 

 (97), 1860. Rathbun, Zoologica, vol. 5, no. 14, p. 159, 1924; Bull. 

 152, U.S. Nat. Mus., p. 139, pis. 62 and 63, and synonymy, 1930. 

 Boone, Zoologica, vol. 8, no. 4, p. 182, fig. 62, 1927. Finnegan, 

 Journ. Linn. Soc. London, vol. 37, p. 630, 1931. Sivertsen, Med. 

 fra det. Zool. Mus., Oslo, nr. 38, p. 13, 1933. 

 Type locality. — Brazil. 

 Type. — Not located. 



Range. — From Port San Bartholome, Lower California (Albatross), 

 to Paita, Peru (Schmitt) ; Galapagos Islands (Williams Expedition) ; 

 4-10 fms; also occurs in the Atlantic. 



Diagnosis. — All spines tipped with black; 4 spines on manus. Basal 

 lobe of antenna prolonged into orbital hiatus. 



Material examined (11 specimens from 10 stations). — 

 33-33. Black Beach, Charles Island, shore, Jan. 27, 1933, 2 males. 

 96a-33. Darwin Bay, Tower Island, fish trap, Feb. 24, 1933, 1 large 



male. 

 101-33. Darwin Bay, Tower Island, shore, Feb. 26, 1933, 1 male. 

 163-34. Black Beach, Charles Island, shore, Jan. 18, 1934, 1 large 



ovig. female. 

 167-34. Post Office Bay, Charles Island, 15 fms, Jan. 19, 1934, chela. 



-34. Charles Island, fish trap, Jan. 19, 1934, 1 ovig. female. 

 177-34. Sulivan Bay, James Island, 5-20 fms, Jan. 23, 1934, 1 male. 

 313-35. Black Beach, Charles Island, shore, Dec. 6, 1934, 1 male 



( photographed ) . 

 339-35. Sulivan Bay, James Island, 10 fms, Dec. 12, 1934, 1 specimen. 

 359-35. Osborn Island in Gardner Bay, Hood Island, shore, Dec. 19, 

 1934, 1 male. 



