WEST INDIAN STAEFISHES 



207 



On the old parts the marginal plates have six or seven slender, 

 acute spines in a transverse row. The upper one is small and 

 sharp ; the second and third are long and subequal ; below these, 

 on the inferior side, are three or four much smaller ones, in a 

 row. Between and around the spines are numerous slender, 

 sharp spinules. 



The inner spine of the adambulacral plate is small and strong- 

 ly curved; the second, on the margin, is nearly straight, about 

 twice as large ; both are compressed. The next two are smaller, 

 acute; they stand nearly side by side, divergent. Outside of 

 these is a rather large, conical, erect pedicellaria on many of the 

 plates. Most of them have three valves; some only two. 



Similar three-valved pedicellariag of larger size occur on the in- 

 terradial areas ; four or five on each. 



Station 2403, off West Florida, in 88 fathoms (No. 10449). 



LuiDiA coxvExiu; cuLA Perrier. 



Luidia convexiuscula Perrier. op. eit., 1881, p. 30; Etoiles de Mer, p. 268, 

 pi. X, fig. 6,27 1884. 



A very slender six-rayed species. The type has the radii 5™™ 

 and 28°^™; ratio, 1:5.6. 



Perrier gives the following characters : 



Dorsal surface slightly convex, with the paxillge almost equal, 

 but a little smaller upon the median part of the rays and on the 

 disk. They bear small, nearly equal, divergent spinules; the 

 central ones are a little larger than the rest, but are not pro- 

 longed into a spine. There are about fifteen rows of paxillse. 



The inferomarginal plates are short, covered with small spines, 

 and bear a single long marginal spine. 



The adambulacral plates have one long, compressed, recurved 

 furrow-spine, and outside of it a cluster of smaller spines. 



Perrier recorded this species from six Blake stations, in 56 to 

 208 fathoms, among the Lesser Antilles, and in one station, in 

 the Gulf of Mexico, in 101 fathoms. 



Some of these specimens were examined by me in 1896. 



27 The references to the figures of this and the preceding species were 

 incorrectly given by Perrier (1884) in his text. 



