92 VERRILL 



On either dorso-lateral side there are similar, but rather sparsely 

 scattered, spines, which mostly show no definite arrangement ; but in 

 some cases, distally, they have a tendency to form about three 

 imperfect rows on each side. These spines are all rather large, up to 

 3 mm. to 4 mm. high, and about i mm. thick, tapered or conical, 

 subacute or acuminate, and often pinched up near the tips and 

 strongly sulcated. They bear large and dense wreaths of minor 

 pedicellariae placed around their bases as dried, and there are numer- 

 ous large, dense clusters of similar pedicellariae thickly scattered 

 over the surface between the spines, and around the papular areas, 

 as if taking the places of the spines that are present in other species. 

 Many of these clusters are as large as those around the spines, or up 

 to 3 mm. to 4 mm. in breadth. They are abundant on both the disk 

 and rays, but become more numerous on the distal half of the rays, 

 where they are often so crowded that in life they must form a 

 nearly continuous coating. Large, stout, erect, dentate, dermal, 

 major pedicellariae are numerous, scattered over the whole dorsal and 

 lateral surfaces of the rays. They are rather quadrangular in an 

 end view; in a side view scarcely compressed, blunt wedge-shaped 

 or stone-hammer-shaped. The tip of the jaws are serrate or 

 unguiculate and subtruncate. The larger ones are about 1.5 mm. 

 high and nearly i mm. broad. 



The pentagon of the disk is formed by five radial clusters of stout 

 conical spines, like the dorsal radials, standing about three together, 

 and five similar interradial groups, standing a little nearer the center. 

 The large, brown madreporic plate takes the place of most of those in 

 one interradial space. A cluster of five spines occupies the center. 



The large dorsal interradial areas of the disk are mostly without 

 spines, but have an abundance of pedicellariae and papulae. 



The upper marginal rows of spines are like the median, but they 

 become more regular and the spines closer together distally. The 

 channel below them is wide proximally, and bears many of the large, 

 serrate pedicellariae and numerous minor ones. The row of infero- 

 marginal spines is strong, double, and regular, each plate usually 

 bearing two spines, especially distally, to the tips of the rays. The 

 distal spines are subacute and sulcate, much like the dorsals, but 

 those on the proximal half are mostly stouter (2 mm. or more), with 

 obtusely rounded and sulcated tips. 



Close to these, but with an intervening papulose channel, is a 

 regular, mostly single row, of peractinal spines, continuous to the 

 tips of the rays. The spines are like the inferomarginals. A 



