CLARK: JAPANESE AND EAST INDIAN ECHINODEKMS. 295 



lapidaria Lyman, 1878. Bull. Mus. Comp. Zool, 5, p. 90. Pacific Ocean, off 

 Japan, 565 fathoms. 



fasciculata Lyman, 1883. Ball. Mus. Comp. Zool., 10, p. 237. Atlantic Ocean, 

 off Barbados, 288 fathoms. 



saurura Verrill, 1894. Proc. U. S. Nat. Mus., 17, p. 288. Atlantic Ocean, off 

 northeast coast of United States, 471-677 fathoms. 



obtecta Liitken & Mortensen, 1899. Mem. Mus. Comp. Zool., 23, p. 119. Pa- 

 cific Ocean, between Panama and Galapagos; vicinity of Galapagos Islands, 

 1201-1360 fathoms. 



sterea Clark", supra. 



Key to variabilis group of Ophioglypha. 1 



Arm-spines 2 or 3 (rarely 4 near base of arm). 



Radial shields in contact for more or less of their length. 2 

 Arm-comb present ; basal upper arm-plates not ridged. 



Lower arm-plates separated by side arm-plates, beyond third joint. 



Arm-spines only 2 radiata. 



Arm-spines more than 2. 



Radial shield clearly longer than broad ; interradial margin of disc not 



nearly filled by a single plate obtecta. 



Radial shield about as wide as long ; interradial margin of disc filled by 



a single plate ornata. 



Lower arm-plates in contact at least to sixth joint. 



Primary plates, radial shield, and two large plates in each interradius 

 practically covering disc; oral shield very large, covering nearly entire 



interbraehial space beneath convexa. 



Disc covered by more than 100 plates ; oral shield covering about two- 

 thirds of the interbraehial space lacazei. 



Arm-comb wanting ; basal upper arm-plates transversely ridged . . saurura. 

 Radial shields completely separated by small plates. 

 Primary plates large ; a single big interradial marginal plate . . . bullata. 

 Primary plates small ; no large interradial plate on margin .... lienosa. 

 Arm-spines 4 or more ; radial plates more or less in contact. 

 Arm-spines 4 or 5. 



1 The species abdita Koehler, 1901, and mundata Koehler, 1906, very possibly 

 belong in this group, but Koehler does not say whether the first pair of tentacle 

 pores opens into the mouth-slit or not, and I am unable to satisfy myself on this 

 point from the figures. Another species (insohta Koehler, 1904) I should certainly 

 have placed here, judging from Koehler's description and figure, but Koehler him- 

 self places it in the group in which the first tentacle pores open into the mouth-slit • 

 I cannot reconcile his figure with such a grouping. 



2 The figure of O. lacazei given by Lyman in the " Challenger " Report (Plate 6, 

 fig. 5) shows the radial shields widely separated, in direct contradiction to the 

 earlier figure (Bull. Mus. Comp. Zool., 5, Plate 3, fig. 69) and to both of Lyman's 

 descriptions. 



