204 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.46. 



LUIDIA GYMNOCHORA, new species. 



Related to L. denudata Koehler, but differing in having constantly 

 11 rays; prominent, central, two-jawed paxillar pedicellarise, together 

 with several small two-jawed pedicellarise on the sides of the pedicels; 

 superomarginal and dorsolateral spinopaxillse distally; with the 

 transverse processes of the regular paxillse longer than the longitudi- 

 nal (the reverse in denudata) ; frequently 3 or 4 inf eromarginal spines ; 

 1 to 5 inf eromarginal pedicellarise; inferomarginals broader actinally, 

 the intervening naked spaces much wider than long, and elliptical to 

 oblong in form ; 1 or 2 pedicellarige on the actinal intermediate plates ; 

 no slender furrow pedicellaria beyond a few plates at base of ray, 

 except rarely and sporadically; second furrow spine compressed; sev- 

 eral subambulacral pedicellarise, the principal one situated adorad 

 of the second and thu'd spme. Rays 11. R = 230 mm., r = 33 mm.; 

 breadth of ray at base, 22 mm,, a short distance beyond base, 28 mm.; 

 rays deciduous, and usually imperfect, the tips being in the process of 

 regeneration or absent; many rays broken into 2 or 3 pieces; rays 

 thin, plane, with very widely open, shallow ambulacral furrows; tube- 

 feet long, sometimes reaching to the margin, and with a small conical 

 button at tip; skeleton loose, dorsal integument thin. 



Type.— Cat. No. 32625, U.S.N.M. 



Type-locality. — Station 5409, between Cebu and Leyte, 20.8 miles 

 southeast of Capitancillo Light, Cebu, 189 fathoms, green mud. 



L. gymnochora — the name referring to the bare spaces between the 

 inferomarginals — is especially characterized by a looseness and flexi- 

 bility of the skeleton which it shares with L. denudata Koehler from 

 the Coromandel Coast, India, 133 fathoms. The most important 

 differences have been enumerated above. 



FamUy BENTHOPECTINID^. 



PECTINASTER HYLACANTHUS, new species. 



Related to P. mimicus Sladen, from which it differs m having the 

 central spines of the paxillse distributed all over the abactmal surface, 

 and in having 13 (exceptionally 12 or 14) adambulacrals correspond- 

 ing to the first 10 inferomarginals. R = 79 mm., r=10.5 mm., 

 R = 7.5 r approximately; breadth of ray at base, 11 to 12 mm. Gen- 

 eral appearance similar to that of P. mimicus; disk small, rays long, 

 slender, recurved at tip; superomargmal plates confined to side wall 

 of ray, with an upright sharp spine close to, or on upper margin; 

 normally no abactmal pedicellarise; abactinal spines numerous and 

 generally distributed; small spinelets in 1 or sometimes 2 circles sur- 

 rounding base of spine ; adambulacral furrow spines 7 or 8 at base of 

 ray; pedicellarise variable, present usually on actmal interradial 



