CLARK: BRITTLE-STARS. 323 



Ophiothrix eurycolpodes, sp. nov. 



eupvs = broad + koXttuStjs = embayed, in reference to the shape of the under 



axm-plates. 



Plate 5, fig. 4. 



Holotype.— M. C. Z., 4,213 and one Paratype, M. C. Z. 3,989. 

 Philippine Islands: southern Luzon, Sorsogon, May, 1912. L. E. 

 Griffin coll. 



Disk, 7 mm. in diameter; arms about 25 mm. long. Disk covered 

 by a large central plate, the big radial shields and 125-150 plates, 

 arranged in three or four series around the central plate, a single series 

 in each radius and in three or four series in each interradius; the radial 

 and interradial plates are greatly elongated; a dozen or fifteen of 

 these disk-plates, and a number of smaller plates at the interradial 

 margins carry smooth, slender spinelets of no great length ; the general 

 effect is a bare, smooth disk. Radial shields very large, triangular, 

 perfectly smooth, separated by the series of narrow radial plates; 

 length equal to about three fourths of disk-radius and distal width 

 about half as much. Upper arm-plates tetragonal, broadly in contact, 

 wider than long; distal margin convex, decidedly longer than straight 

 proximal edge. Interbrachial areas below nearly naked, carrying 

 only a few small plates each of which bears a smooth, slender spinelet. 

 Oral shields much wider than long, diamond-shaped, all angles 

 rounded; proximal sides more or less concave, distal sides lightly 

 convex. Adoral plates somewhat widened distally, but much longer 

 than wide, scarcely or not meeting interradially. Oral plates very 

 large with huge pores. Tooth-papillae numerous and small. First 

 under arm -plate small, more or less triangular, about as long as wide; 

 second and third plates, squarish with rounded corners, longer than 

 wide; succeeding plates wider than long, with proximal margin 

 straight and distal margin more and more conspicuously concave 

 (or broadly embayed); owing to this concavity of the distal margin 

 the plates are in contact only at the corners. Side arm-plates very 

 small, not meeting either above or below; each carries a series of 

 4 or 5 long, slender, rather glassy arm-spines; the lowest is very 

 small, the next much longer, and the third and fourth are twice as 

 long as the width of arm; if a fifth is present it is shorter than the 

 fourth; on the first arm-segment outside the disk a sixth, still smaller 

 5pine may be present; the sLxth and fifth spines are smooth and 



