CLARK : THE CIDARIDAE. 207 



plish, but may be reddish or greenish. Originally discovered by the " Challenger " 

 near Amboiua, this species has since been taken only by the" Albatross" in 

 Sagaini Bay, Japan. Its bathymetric range is 15-114 fins. 



Tretocidaris reini. 



Cidaris (Dorocidaris) reini Doderlein, 1887, Jap. Seeigel, p. 7. 



Plate 4, figs. 1-7, Jap. Seeigel, Dolderlein,1887. Plate 1, figs. 3, 3, Siboga-Exp. Ech., 



de Meijere, 1904. 



Although this species is closely related to the preceding, the material at hand 

 supports Ddilerlein's opinion that his Japanese specimens were a new species; 

 curiously enough, however, he makes no reference whatever to bracteata! The 

 primary spines of the two species are quite distinct, as already shown; the ocular 

 plates of reini are narrower and higher than in bracteata and more broadly in 

 contact with the anal system, and the difference in color is very marked ; when 

 reini is not uniformly yellowish with dull white spines, the uppermost coronal 

 plates, the interambulacral miliary spines, the genital plates and the anal system 

 are deep reddish, while the ocular plates and ambulacra with all their spines are 

 pale yellowish in marked contrast, just the opposite of the coloration in bracteata; 

 the primaries of reini are apparently not banded or spotted in adults, but if 

 de Meijere' s identification of his small East Indian specimens is correct, the young 

 must be very much like those of bracteata. In size and in the pedicellariae, the 

 two species agree well; the largest reini reported is 34 mm. h. d. Excepting the 

 four young Cidaroids taken by the "Siboga" near the Kei Islands and Timor 

 which de Meijere refers to this species, but which might just as naturally be called 

 bracteata, reini has not been taken yet anywhere but in Sagami Bay and Ka- 

 goshiina Gulf, Japan, in 83-158 fths. 



DOROCIDARIS- 

 Dorocidaris A. Aga&siz, 1869, Bull. M. C. Z., 1, p. 254. 



Test much as in Tretocidaris, but ranging up to only .70-.75 h. d. Abactinal 

 system very different, its outline not often sharply defined and rather irregular, 

 with reentering angles between genital and ocular plates; latter more or less pen- 

 tagonal and deeply notched hy ambulacra. Primary spines cylindrical, at least near 

 base, or terete, sometimes smooth, but usually with longitudinal series of granules, 

 or ridges, never " winged " however, and generally not flaring at tip. Globiferous 

 pedicellariae, both large and small, with a conspicuous end-tooth on the valves ; 

 tridentate pedicellariae usually present. 



Although this genus is quite easily distinguished from the preceding, the line 

 of division between it and Stereocidaris is exceedingly hard to draw, and it is an 

 open question whether there is sufficient ground for keeping them separate. As 

 small genera are more convenient and wieldy, however, we may retain the division 

 recognizing that the line is a very arbitrary one. As here used, Dorocidaris in- 

 cludes five species, which are found only in the Atlantic Ocean and almost entirely 



