306 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



of the spine between the collar and the ridges is very conspicuous 

 being smooth and shining and of a pinkish color. The oral primaries 

 are slightly curved, flattened, slightly broadened, with the edges 

 fairly distinctly serrate. They have a couple of conspicuous ridges 

 on both the oral and aboral side; only the innermost may be quite 

 smooth on both sides. The third is transitional to the ambital spines. 



The scrobicular spines are about 3 mm. long, rather thick, with 

 the outer side slightly convex and the inner side concave with a 

 median ridge. The sides are straight, not narrowing toward the end, 

 which is slightly rounded. The marginal ambulacra! spines are about 

 2 mm. long, narrow, straight, and slightly flattened; near the peri- 

 stome they are somewhat broadened and concave toward the end. 

 The miliary spines are simply spine-shaped, very conspicuously 

 smaller than the scrobicular and marginal ambulacral spines; tran- 

 sitional sizes are scarcely to be found around the scrobicular ring. 

 The miliary spines are rather erect, the others appressed. 



Large globiferous pedicellariae are very scarce; their valves (pi. 78, 

 fig. 14) are long and very narrow, with a small subterminal opening, 

 the outermost teeth of which join so as to form an apparently unpaired 

 end tooth. The stalk is very short and simple. The small globiferous 

 pedicellariae (pi. 78, fig. 13) likewise have narrow and rather elongate 

 valves of very simple structure. No tridentate pedicellariae were 

 observed. ' 



The spicules are of the usual stereocidarid shape. 



The primary spines are of a slightly pinkish tint, tne portion between 

 the collar and the ridges being more conspicuously pink. The 

 secondaries are brownish. The naked test is pure white. 



Remarks. — This form evidently is so closely related to Stereocidaris 

 sceptriferoides Doderlein that it might well be questioned whether it 

 should not simply be designated as sceptriferoides. The shape of the 

 primaries, however, seems to be rather conspicuously different, judg- 

 ing from Doderlein's description and figures. The scrobicular spines 

 also would seem to be different, judging from the description of 

 sceptriferoides, and likewise the shape of the large globiferous pedi- 

 cellariae is not in accordance with the figure given by Doderlein. It 

 is very possible that these and the other minor differences which 

 according to the descriptions exist are no more than what may well 

 be found within the limits of the species; but so long as no material 

 has been brought to light to show this species to be so variable, it 

 does not seem justifiable simply to unite the form from the Philippine 

 Sea with the Japanese species, which is not yet known from beyond 

 the Japanese seas. In view of the insufficient knowledge of S. 

 sceptriferoides I have thought it well to give a full description of the 

 specimen at hand, be it simply identical with the Japanese species, 

 or a separate variety, or perhaps a distinct species. 



