THE ECHINODERMS OF CEYLON. S7 
upper distal surface. Adambulacral armature much as in 
Stellaster, with a conspicuous, flattened, blunt spine on actinal 
surface. (Name from ctodc, a pit in the ground for storing corn 
-+ astho, a star ; in reference to the papular pores surrounded 
by conspicuous granules.) Genotype—S. tuberculatus, sp. nov. 
It is with much diffidence that I add a new genus to the 
perplexing family Goinasteride, but I cannot otherwise 
dispose of the present species and Studer’s Sfellaster squamu- 
losus. That the two are congeneric will not, I think, be 
questioned ; that they cannot properly be placed in Stellaster 
seems to me equally true. Neither has the plates concealed 
by skin, although squamulosus is nearer true Stellaster in this 
respect than is tuberculatus. More important is the fact that 
neither has the characteristic spine on the inferomarginals, 
which is so conspicuous even in very young specimens of 
Stellaster. And finally, neither has the arched disc and slender 
pointed rays characteristic of Stellaster. Superficially the 
two species are much like Goniodiscus forficulatus, Perrier, but 
in that species (whose generic position, by the way, is quite 
uncertain) the medioradial plates do not reach the terminal 
plate of the arm, the papule are not surrounded by enlarged 
granules, and the adambulacral armature is in three parallel 
series, and has no conspicuous actinal spine. 
Specific diagnosis: Body markedly stellate, flattened. 
R = 33 mm., r= 14 mm., and Br. (at base of arm) = 15 mm. 
R=2-4r. Abactinal plates granulated, but the outlines of 
the separate plates plainly visible. Proximal medioradial 
plates and some interradial plates, each with a more or less 
conspicuous tubercle ; altogether there are about fifty such 
tubercles on the holotype, the largest being on the fourth and 
fifth medioradial plates. Many plates which lack a tubercle 
have three or four central granules noticeably enlarged. 
Granules around the papular pores distinctly larger than those 
on the neighbouring plates. Superomarginal plates, 11 on 
each side of each ray, decreasing steadily in size distally, but 
becoming more and more swollen ; central granules of each 
