106 BULLETIN 76, UNITED STATES NATIONAL MUSEUM. 



paxilhB but frequently lar-er; inferomarginuls with a transverse series of spines 

 or sninelets- fasciolar channels deep and wide; actinal intcrradiai area very small; 

 actinal intermediate plates extending nearly to tip of ray in a smgle series (excep- 

 tionally two or three series are present, and plates rarely absent), the mferomar- 

 ginals intermediate plates and adambulacrals corresponding in a transverse series. 

 Papuhu compound, i. e., with distal portion subdivided into numerous papilla;. 

 Pcdicollnriw frequently present, sessile, two or three jawed as a rule, either conical, 

 tong-sliaped or low and bivalved. Tube-feet in two rows, without true sucking 

 disks. Superambulacral plates present, well developed. Anus and intestinal 

 coecum absent. Gonad in numerous tufts forming a linear series, all along either 

 side of abactinal integument. 



KEY TO THE SPECIES OF LUIDIA HEREIN DESCRIBED. 



a'. Lateral abactinal paxilla; with a quadrate or subquadrate tabulum. 



5". No pediccllaria;; abactinal surface drab gray or greenish gray in life foliolata, p. 106. 



6^ PediccUariiE (bivalved) on inferomarginal plates (abactinal end) and on superomarginal paxillse, 

 and trivalved upright pedicellariie on actinal intermediate plates; abactinal surface reddish in 



life, BOinctimes mottled with lighter hidwigi, p. 113. 



a'. Paxilla; with stellate crown; granuliform abactinal two-jawed pedicellarise; slender two-jawed 

 actinal intermediate pedicellaris; rather prominent lateral spines asthenosoma, p. 116. 



LDIDIA FOUOLATA Grube. 



PI. 19, figs. 1-3; pi. 21, figs. 3-5; pi. 54, fig. 3. 



Luidia foliolata Grube, 43. Jahresber. d. schles. Ges. vaterl. Cultur, Breslau, 1866, p. 69 (no 

 locality).— LuDWio, Mem. Mu.s. Corap. Zool., vol. 32, 1905, p. 80.— Fisher, Proc. Wash. 

 Acad.Sci., vol. 8, 1906, p. 121. 



Luidia foliata Sladen, Challenger Asteroidea, 1889, pp. 247, 742. 



Diagnosis. — From a large specimen, station 4457. E=222 mm.; r = 28 mm.; 

 R = 8.64r. Breadth of ray at base, 32 mm. Rays five, long, evenly tapered to a 

 sharp but not attenuate extremity; abactinal surface of rays compact, well arched 

 but subplane along median area; interbrachial angles acute; rays constricted at base. 

 No pediccllariae. Abactinal paxilliB quadrate along either side of ray forming four 

 regular series; much smaller and irregular on median portion of ray. Abactinal 

 plates cruciform. Inferomarginals broad with a transverse row of three flat- 

 tened lanceolate pointed or blunt spines on outer half of plate; other spinelets 

 slender, not squamiform and chaffy. Adambulacral plates well spaced; armature 

 as follows: One saber-shai)ed furrow spine and on actinal surface three to five 

 slender, slightly tapering, bluntly pointed spines, accompanied by a variable num- 

 ber of much smaller spinelets. Actinal intermediate plates in a single longitudinal 

 series on ray, each bearing a tuft of spmelets but no pedicellarias. Mouth plates 

 with a compact group of numerous small spinelets on face toward actinostome, 

 and numerous spines on exposed surface. Color, oUve drab or pinkish gray, usually 

 the former. 



Description. — Abactinal paxilla; quadrate along either side of ray, formmg four 

 regular series and decreasing in size toward median area of ray where the paxillae 

 are small, irregular, and not arranged in series. Superomarginal paxilla largest, 



