166 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



cellariae on the interradial plates (in one of them, not on all). The 

 other specimens entirely lack pedicellariae, such as are present in 

 forfcifera. 



The mouth plates form a salient angle into actinostome. and at 

 the inner end of each pair of plates are 2 large two- jawed pedicel- 

 lariae half as long as the interradial width of the plate and extend- 

 ing side by side horizontally over actinostome. Seen from the actinal 

 surface they are slightly tapering, bluntly pointed. Six to eight sharp 

 spines occupy the outer margin between the pedicellaria and outer 

 end of plate, and about the same number, close to the above, follow 

 the margin of the narrow median suture. 



Type.— C?it. No. 32622, U.S.N.M. 



Type-locality. — Station 5181. off eastern Panaj'^ (6.6 miles northeast 

 Antonia Island), 26 fathoms, mud and fine sand, surface temperature 

 80° F. ; 6 specimens (4 young). 



Distribution. — Panay to Tawi Tawi Group, 12 to 26 fathoms. 



Specimens e.ramined.—^me — 6 from the type-locality, 2 without 

 locality, and 1 from station 5158, 1.9 miles southeast of Tinakta 

 Island, Tawi Tawi Group, Sulu Archipelago. 12 fathoms, coarse 

 sand, shells. 



Remarks. — L. prlonota., on account of the absence of adambulacral 

 pedicellariae and the large number of adambulacral spines proxi- 

 mally can not be confused with L. forfiGifera or L. quhiaria (includ- 

 ing L. limhata). It differs from L. penangensis de Loriol, which 

 has constantly 6 rays, and a prominent madreporic body, in having 

 larger paxillae, in lacking adambulacral pedicellariae, and in having 

 more than 3 adambulacral spines. Luidia chefuensis Grube is ap- 

 parently a museum name only. According to Sladen (1889, p. 253) 

 it has not been described. This form is said b}'^ Sladen to have a 

 comb of 4 or more spinelets, running parallel to the furrow, behind 

 2 single curved spinelets, apparently in the position occupied by 

 the inner pair of spines of prlonota. 



The absence of adambulacral and abactinal pedicellariae suggests 

 Luidia clathrata of the West Indies and southern United States, 

 and L. foUolata (southern Alaska to Mexico). 



LUIDIA ORIENTALIS Fisher. 



Plate 43, figs. 2-4 ; plate 44, tig. 1 ; plate 4f5, tig. 3. 



Luidia orientalis Fisher, 191 3e, p. 203. 



Diagnosis. — Kelated to L. sarsi Diiben and Koren, L. africana 

 Sladen. and Z. astJienosoma Fisher. Closely resembling L. af<theno- 

 soma^ from which it differs in having deeper and broader marginal 

 fascioles, slightly longer inferomarginal and adambulacral spines, 

 longer inferomarginal spinelets, and actinal intermediate pedicel- 



