336 VERRILL 



LUIDIA LUDWIGI Fisher. 



Luidia ludwigi Fisher, op. cit., igo6, p. 122; op. cit, 1911&. P- Ii3> pl- xx, 

 figs. 2, 3; pi. XXI, fig. 2; pi. Liv, figs. 2, 20. 



Rays five, long and narrow. Radii, 13 mm. and 107 mm. ; ratio, 

 1 : 8.2. Abactinal area of rays has three or four rows of quadrate 

 paxillae on each side. 



The superomarginal plates have small trivalve and bivalve pedi- 

 cellariae. 



The inferomarginals have a similar pedicellaria on the upper end, 

 and one to three, mostly two, lateral spines, and three to six 

 enlarged spinelets, on the lower side, with small spinelets over the 

 general surface. 



The peractinal plates extend to half the length of the ray; and 

 like those of the interradial areas, each has a rather prominent three- 

 valved pedicellaria. 



The adambulacral plates have a curved furrow-spine, three spines 

 on the actinal side, and one or two smaller spines (Fisher). 



According to Dr. Fisher, this species occurs from Monterey Bay 

 to Santa Barbara Islands and San Pedro, California, in 15 to 50 

 fathoms, mostly on bottoms of mud or sand. 



LUIDIA ASTHENOSOMA Fisher. 



Luidia asthenosoma Fisher, op. cit., 1906, p. 124; 1911&, p. 116, pi. xx, fig. i ; pi. 

 XXI, fig. I ; pi. LIV, fig. I. 



Rays five, very long, slender, flattened, fragile, with a small disk. 

 Radii, 9 mm. and 86 mm. : ratio, i : 9.5 ; width of ray at base, 

 10 mm. to IT mm. 



Inferomarginal* plates narrow, forming the margins of the ray, 

 but not extending much on the dorsal surface, each with a transverse 

 row of three large, sharp, acicular spines, and covered with very 

 slender spinules ; fascioles deep and wide. 



The adambulacral plates have a transverse row of three prominent 

 spines, the inner one being a saber-shaped furrow-spine. The inter- 

 actinal or peractinal plates have a bivalved. short, blunt, papillifomi 

 pedicellaria. 



The dorsal paxillae are stellate ; some have two-valved, or some- 

 times three-valved, pedicellariae. The superomarginal plates are 

 about twice the size of the adjacent paxillae. The oral plates have 

 bivalved pedicellariae (Fisher). 



Dr. Fisher records this species from thirty- four localities, in 11 to 

 339 fathoms, between Monterey Bay and Los Coronados Islands, 

 Lower California. 



