Boone, Echinodermata, Cruises of "Eagle" and "Ara," 1921-28 11 



the"Ara" specimens have nine rays each. Specimens with only eight 

 rays have been recorded. 



Rays nine, very long and slender, gradually tapered. R = 160 mm., 

 r = 18 mm. Disk small, circular, interbrachial angle acute. Abactinal 

 surface covered with close-set paxillae; those of the center of the 

 disk and median area of the rays being much the smaller; in shape 

 the smaller paxillae are nearly circular or oval; the spines are short 

 with blunted convex tips, covered with small, rounded granules. The 

 larger dorsolateral paxillae of the rays are in three series on each 

 side and the paxillae are oval with 35 to 50 short rounded 

 granulose spinules. In the interradial area the larger paxillae form 

 a triangular area. The inferomarginals are densely covered with 

 short, flat spines, larger toward the middle, and each plate bears two 

 larger, acuminate, biserial marginal spines. The adambulacral plates 

 bear three or four stout, tapered, laterally compressed spines, the 

 inner two of each plate being curved and more acuminate than the 

 others. The jaw angle bears 18 to 24 slender, long spines, 10 to 12 

 of which are paired in series, one above the other at the apex. 

 References: Stella marina Marcgraf, George, Hist. Rerum Nat. 



Brasiliae, vol. VIII, p. 189, 1648. 

 Asterias 4. "The large starfish with eight or more slender arms," 



Patrick Browne, Civil and Natural History of Jamaica, p. 393, 



1756. 

 Luidia marcgravii Lutken, Vidensk. Meddel., series 2, vol. I, p. 43, 



1859 (issued 1860). — Verrill, Trans. Conn. Acad. Arts and Sci., 



vol. I, p. 343, 1867 ; Bull. Labr. Nat. Hist. S. Univ. Iowa, vol. VII, 



no. 1, p. 208, pi. 5, fig. 1, 1915. 

 Luidia senegalensis Steenstrup, Mss. in the Copenhagen Museum. — 



Muller and Troschel, Syst. der Asterid., p. 78 (in part), 1842. 



(Not Lamarck.). — Perrier, Arch. Zool. Exper. de Gener., vol. V, 



p. 262, 1876. — Richard Rathbun, Trans. Conn. Acad. Arts and 



Sci., vol. V, p. 149, 1879. 



Luidia Columbia (J. E. Gray). 

 Plates 37 and 38. 



Type: Gray's type came from St. Bias, collected by H. Cuming, 

 and is deposited in the British Museum. 



Distribution: A littoral species known from Magdalena Bay, 

 Lower California and the Gulf of California, southward as far as 

 northern Peru ; also found in the Galapagos Archipelago. 



