128 NATUEAL HISTORY BULLETIN 



fourth plate is larger than the others; those of the two more 

 proximal plates are much smaller ; none on the first. 



Inferomarginal plates have a marginal spine much larger than 

 the others, surrounded at base by several smaller spines less than 

 half as long ; otherwise the plate is covered with small spinelets. 



The dorsal paxillse are rather small, covered with equal small 

 spinules. About fifteen long, slender, acute spines surround the 

 center of the disk. Madreporic plate is small, prominent, round- 

 ed, pretty coarsely grooved, situated near the marginal plates. 



The interactinal plates are in a single series with small spines. 

 (No pedicellarise are mentioned.) The adambulacral plates bear 

 a semicircular row of nine graded marginal spines, and a single 

 straight, long, slender, acute spine on the actinal face. 



The jaw-plates bear, each, ten marginal spines, decreasing 

 from the oral end backward, and also some small epioral spines, 

 both on the surface and bordering the naked sutural area be- 

 tween them. 



The papular pores are not mentioned by Perrier, nor any ped- 

 icellariae. 



So far as his description shows, there is no character by which 

 this form is distinguishable from typical C. mirahilis, but a re- 

 examination of the type is desirable, especially with reference to 

 the papular arrangement and the special characters of the dorsal 

 parapaxillae. 



Among my notes, made w^hen I examined the Blake collection, 

 in 1899, there is no mention of the type of this species. Prob- 

 ably I did not see it. Most likely this is only a slight variation 

 from the typical form of the original 0. mirahilis, as suggested 

 by Perrier himself, in 1894. The only point worthy of note, in 

 the description of Perrier, is the apparently more spinose condi- 

 tion of the inferomarginal plates, in this respect approaching 

 those of C. eckinulatus. Perrier gave only two localities : station 

 2, off Havana, in 805 fathoms, and station 19, off "West Florida, 

 in 310 fathoms (one very young). 



21 Perrier says third and fourth plates, evidently by an error, for second 

 and third. In this respect his description, when corrected, applies well to 

 his figure, pi. ix, fig. 4 = C. mirdbilis. 



