416 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



O. sanctum) that the two ophiurans can not belong to the same 

 species and that they differ not only in the arrangement of the plates 

 of the dorsal surface, but also in the characters of the ventral sur- 

 face. The new species differs from O. simplex as that species was 

 described by Lyman in the radial shields, of which the proximal 

 portion is produced into a very sharp angle, and in the great devel- 

 opment of the ventral interradial plate which follows the mouth 

 shield, of which the distal border is very convex. But it is especially 

 remarkable for the very peculiar form of the genital slits, a form 

 which is not met with in any other species of the genus Ophio-musiitm, 

 and which appears to me to be quite characteristic. 



OPHIOMUSIUM PROPERUM Kcehler. 



Ophiomusium propcrum KCEHLER ('04), p. 62, pi. 10, figs. 11-13. H. L. 

 CLARK ('15), p. 334. 



Locality. Albatross station 5646; Buton Strait; North Island 

 (S.) bearing S. 68 E., 13.90 kilometers (7.5 miles) distant (lat. 5 

 31' 30" S., long. 122 22' 40" E.) ; 834 meters (456 fathoms) ; De- 

 cember 16, 1909 ; gn. M. 



One specimen (Cat. No. 40994, U.S.N.M.). 



Notes. The diameter of the disk is 10 mm. 



This specimen agrees well with the types collected by the Siboga 

 in the Sunda Archipelago between 0-7 S. latitude and 117-119 

 E. longitude, in 695 to 724 meters (383 to 497 fathoms), in which 

 the diameter of the disk varied between 11 mm. and 12 mm. 



OPHIOMUSIUM RELICTUM Kcehler. 



Plate 91, figs. $-8. 



Ophiomusium relictum KCEHLER ('04), p. 61, pi. 10. figs. 5-7. H. L. CLARK 

 ('15), p. 334. 



Locality. Albatross station 5651; Gulf of Boni, Celebes; Bugin- 

 kali Point bearing S. 67 E., 38.91 kilometers (21 miles) distant (lat. 

 4 43' 50" S., long. 121 23' 24" E.) ; 1,280 meters (700 fathoms) ; 

 December 17, 1909. 



One specimen (Cat. No. 40919, U.S.N.M.). 



Notes. The diameter of the disk is 9 mm. One of the arms, which 

 is preserved for its entire length, measures 35 mm. 



The specimen agrees well in its principal characters with the 

 types which were collected by the Siboga in 0-7 S. latitude, 117- 

 119 E. longitude, at depths between 695 and 724 meters (383 to 396 

 fathoms), and in which the diameter of the disk varied between 11 

 mm. and 12 mm. The Albatross specimen differs from them only 

 in having the tuberosities of the dorsal plates of the disk more 

 marked and in having the arm spines a little more developed. I in- 

 clude on plate 91 as figures 6-8 photographs of the two surfaces 

 of the disk, and a side view of the arms. 



