102 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



Actinai intermediate plates extend in a single series three-fourths 

 the length of ray or to withm 13 inferomarginals of the tip; in 2 

 series not quite half, and in 3 only to the fifth inferomarginal. 

 There is no unpaired interradial series of plates except near the 

 margin where 1 or 2 plates are interradial; these are met by paired 

 series from the mouth plates or first adambulacrals. Or there may 

 be an unpaired plate behind the combined mouth plates and another, 

 widely separated, near the margin. The plates bear coordinated 

 groups of 5 to 10 short pulpy spatulate or clavate papillae, borne 

 on low tabula, and are separated into series by channels running 

 from the interadambulacral sutures to the margin. 



Adambulacral plates with strongly angular furrow margins, of 

 which the aboral facet is slightly the larger. Furrow spines 7 or 

 8 proximally and 6 or 7 distally. They form a palmate series, the 

 median the longest, and compressed with edge ty furrow; the 

 laterals with the surface to furrow. All are blunt with a slight 

 membranous swelling at tip. The aboral member is often trun- 

 cate. The subambulacrals are shorter, pulpy, clavate, or inverted- 

 clavate, similar to the spinelets of the actinai intermediate plates. 

 The calcareous spine is also club-shaped. They are usually arranged 

 in 2 longitudinal series with about 5 spines in each. The first 

 and second plates are much compressed, the first bears about 20 

 spines in 2 closely appressed transverse series. 



Mouth plates much compressed and prominent actinally, the 

 combined pair a little over twice as long as wide with a wide median 

 suture of nearly uniform breadth throughout. Armature (1) at 

 the inner angle of each plate a large oblong or oval leaflike tooth 

 with a smaller one at the side sometimes nearly as long; (2) a mar- 

 ginal series of about 12 small strap-shaped truncate or round-tipped 

 spines extending three-fourths the distance to outer end of plate, 

 and appressed against a series of about 12 heavier, often clavate, 

 but stubby spines, following the border of the suture. Except for 

 the inner teeth each mouth plate resembles an enlarged first adam- 

 bulacral. 



Madreporic body small, a little nearer margin than center, and 

 traversed by coarse striae. 



Type.— Cat. Xo. 30517, U.S.N.M. 



Type-locality. — Station 5468, Lagonoy Gulf, southeastern Luzon, 

 569 fathoms, green mud; one specimen. 



Distribution. — Known only from Lagonoy Gulf, off southeastern 

 Luzon, 560 to 569 fathoms. 



Specimens examined. — Three: one from type-locality and one 

 from each of the following stations: 



Station 5460, Lagonoy Gulf, 565 fathoms, gray mud. 



Station 5i70, Lagonoy Gulf, 560 fathoms, mud. 



