NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK. 187 



Locality. Albatross station 4979, off eastern Japan, lat. 33 53' N.; 

 long. 137 42' E., 943 fathoms, brown mud, fine sand, foraminifera, 

 bottom temperature 36.4, 1 specimen. 

 Type. Cut. No. 25636, U.S.N.M., from station 4979. 



The groups of granular papillae near the distal end of the jmouth 

 slits are very peculiar, giving a characteristic appearance to the oral 

 region, and indicate a possible relationship to Ophiocamax lithosora. 

 Whether the sunken 

 appearance of the ra- 

 dial shields and the 

 correspondingly re- 

 markable division of 

 the disk into fifteen 

 wedge-shaped parts 

 is characteristic of 

 the species or only an 

 accentuated individ- 

 ual peculiarity can 

 not, of course, be de- 

 termined without 

 more material. But 

 it is hard to doubt 

 that the main fea- 

 tures of the peculiar 

 disk will be found to 

 be characteristic of 

 the species. 



OPHIOMITRA POLYA- 

 CANTHA, new species.** 



Disk 6 mm. in di- 

 ameter; arms about 

 30 mm. long. Disk 

 circular, covered 

 with numerous 

 small, rather regular 

 scales, many of which 

 bear each a low, thorny stump. Radial shields small, triangular or 

 squarish, about as wide as long, distinctly separated. Upper arm 

 plates small, rhombic or triangular, with convex distal margin, widely 

 separated from each other; between the upper arm plates the arm is 

 somewhat constricted. Interbrachial spaces below, covered with 



FIG. 86. OPHIOMITRA POLYACANTHA. x 8. a, FROM ABOVE; 6, FROM 

 BELOW; c, SIDE VIEW OF TWO ARM JOINTS NEAR DISK. 



signifying many and aKavda, signifying spine, in reference to the large 

 number of arm spines. 



