628 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 43. 



numerous, crowded, and coarser central granules, and slenderer 

 peripheral granules; and in having narrower adambulacral plates, 

 which lack the characteristic fasciolate pedicellarise of ctenipes, 

 except in a less specialized form on the first few plates. R = 45 mm., 

 r = 12.5 mm., E, = 3.6 r; breadth of ray at mid-interbrachium, 14 

 mm, ; at distal margin of fourth superomarginal (the proximal end of 

 the slender portion of ray) 8 mm., or length of first 5^ superomarginals 

 measured on ambitus. Abactinal plates strongly tabulate with 

 convex, subhexagonal or roundish crowns, havmg in the radial series 

 18 to 25 close-set, coarse, irregularly polygonal, central granules and 

 20 to 25 smaller, slenderer, peripheral ones; plates of the single 

 (radial) series which separate superomarginals of ray, shghtly tabulate 

 proximally, longer than wide throughout, with granules similar to 

 those of the plates of disk, and all narrower than the radials of disk; 

 superomarginals broad, all wider than long, slightly tumid, with 

 close-set, coarse, polygonal granules; inferomarginals v/ith sub- 

 squamiform granules ventrally and 2 or 3 short appressed lanceolate 

 spinules in a group or transverse series on inner half of the proximal 

 plates; adambulacrals only a trifle wider than long, with angular 

 furrow margin, and 7 or 8 furrow spmes in a palmate series; first 4 

 plates with aboral facet of margin much the longer; subambulacral 

 spinelets 12 to 15 with 1 enlarged, tapering, sharp spine; oral spines 

 8 or 9, on angular margin of mouth plates, those at apex of angle the 

 shortest. 



Type.— Cat. No. 30537, U.S.N.M. 



Type-locality. — Station 5289, Verde Island Passage, north coast 

 of Mindoro, 172 fathoms, broken shells, sand. 



PERISSOGONASTER, new genus. 



Differing from Paragonaster in having an odd interradial marginal 

 in both series, and an incomplete odd interradial series of actinal 

 intermediate plates; papulse distributed all over disk and as far 

 along radii as the adradial plates extend. 



Type of the genus. — Perissogonaster insignis, new species. 



PERISSOGONASTER INSIGNIS, new species. 



Similar in general appearance to a Paragonaster with unusually 

 large disk, stout rays, and the adradial plates extending in large 

 specimens a third to two-fifths length of ray. R = 113 mm., r = 35 

 mm., R = 3.2 r; breadth of ray at mid-interbrachium, 40 mm., thence 

 tapering gradually to the bluntly pointed extremity; interbrachia 

 wide and arcuate; superomarginals 37 to 42, broader than long, and 

 increasing slightly in width up to the tenth or twelfth, and beyond the 

 eighth to seventeenth separated only by the rectangular carinal 

 plates; odd interradial plate similar to the rest; plates covered with 

 depressed, roundish, convex, slightly spaced granules, the outer end 



