no. 1827. NEW GENERA OF STARFISHES— FISHER. 421 



PONTIOCERAMUS GRANDIS, new species. 



Kays 5. R = 160 inm., r = 70 mm.,R = 2.3 r; breadth of ray at 

 mid-interbrachium, 80 mm. Disk very large, arcuately pentagonal 

 and produced into short pointed rays. Abactinal plates numerous, 

 with a very smooth and slightly convex surface, on the radial region 

 regularly hexagonal, and on center of disk and in about 9 longitu- 

 dinal (radial) series distinctly tabulate, each tabulum surrounded by 

 6 papulae, the area of tabulate plates reaching about two-fifths R. 

 The papular areas are proximally considerably wider than the area 

 of obviously tabulate plates. Interradial plates flat, irregularly four 

 to six-sided. All abactinal plates surrounded by a single series of 

 flat squarish granules, set in membrane and flush with surface of 

 plate, those on the radial plates hard to see, and larger on the lateral 

 than on the transverse margins of tabulum. 



Marginal plates conspicuous. Superomarginals (30 to a ray) form 

 an even bevel in interbrachium, but on ray a rounded angle, being 

 there somewhat wider than high. Inferomarginals on the contrary 

 encroach more conspicuously upon actinal surface in interbrachium 

 than on ray, but like the superomarginals the angle between lateral 

 and ventral surface is more pronounced on ray. Superomarginals 

 with one, and inferomarginals with two or three series of small flush 

 granules forming an inconspicuous border, and in addition a variable 

 number of scattered granules on the lateral face of plates, all flat 

 and sunken flush with the level of plates. 



Actinal intermediate plates very numerous, those nearest furrow 

 largest, and the only ones at all regularly arranged. They are closely 

 granulate, the granules flat and immersed in thin membrane. The 

 plates next to adambulacrals bear one or two small rather delicate 

 bivalved pedicellarise, whose denticulate jaws are slightly wider than 

 high (the larger ones) or as wide as high (smaller) and fit into slight 

 depressions when open. 



Adambulacral plates proximally long and narrow, very gradually 

 widening on outer half of R, until near tip; beyond the last actinal 

 intermediate plates they are as wide as long. Each plate is angular 

 toward furrow, the angle being sharper deep in furrow than on 

 margin, and is usually adoral to the middle of plate, varying in 

 position between the middle and adoral margin of plate. Furrow 

 spinelets 11 or 12, stout, short, round-tipped or blunt, much flattened, 

 those near the angle of margin with edge to furrow, the others with 

 flat side thereto. The aboral spinelet of the series is the broadest 

 and stoutest, and often the adoral spinelet is similarly enlarged. 

 The spinelets are subequal in length, or the median slightly the 

 shorter. The actinal surface proximally is wide enough for only one 

 longitudinal series of unequal granules, but as the plate widens more 



