OPHIUKANS OF THE PHILIPPINE AND ADJACENT WATERS. 403 



Ophiomusium facundum can not be confused either with the species 

 which I have described above under the name of O. facetum, in which 

 the arm spines are more numerous, seven or eight in number at the 

 base of the arms, and very regularly disposed along the distal border. 

 Furthermore, in O. facetum the dorsal plates of the disk are entirely 

 smooth, the under arm plates are entirely lacking beyond the third, 

 and the large ventral interradial plate which follows the mouth shield 

 is less developed. 



The large specimen from station 5623, of which I have spoken 

 above, in which the granules are very much less developed on the 

 plates of the dorsal surface of the disk and in which the arm spines 

 are more numerous, may seem rather close to O. facetum, but there 

 are nevertheless very considerable differences. I find in this speci- 

 men that the large ventral interradial plate reaches a very consider- 

 able width at the periphery of the disk, the under arm plates are 

 continued throughout the whole preserved portion of the arms, the 

 small group of two ventral spines is always very recognizable and 

 very distinct whatever may be the number of other spines, and the 

 granulation of the dorsal surface of the disk, though less developed, 

 is no less evident. 



OPHIOMUSIUM FIMBRIATUM. new species. 



Plate 90, figs. 6-8. 



Locality. — Albatross station 5614; Molucca Passage; Tifori Island 

 (C.) bearing N. 19° E., 56.52 kilometers (30.5 miles) distant (lat. 

 0° 31' 00" N., long. 125° 58' 45" E.) ; 2,011 meters (1.100 fathoms) ; 

 November 22, 1909 ; gy. M., S., Glob. 



One specimen (Cat. No. E. 188, U.S.N.M.). 



Description. — The diameter of the disk is 20 mm.; the arms are 

 incomplete ; one of them is preserved over a length of 40 mm. They 

 are rounded, rather narrow, and measure 4 mm. in width at the base. 



The disk is pentagonal with the sides straight ; the dorsal surface 

 is plane, the ventral surface is somewhat swollen, and the borders 

 are rounded and somewhat sharpened. The dorsal surface is covered 

 in the central region with numerous small rounded nonimbricated 

 subequal plates, among which it is impossible to find the least indica- 

 tion of primary plates. These plates become larger, and especially 

 they elongate, in the radial and interradial spaces. In the radial 

 spaces they are arranged in three or four rows which separate the 

 two radial shields of each pair for their entire length. In the inter- 

 radial spaces they form four to five rows, the median ones being a 

 little larger than the others. Toward the periphery of the disk there 

 is a large, transversely broadened, triangular plate which is much 

 arched and three times as broad as long, beyond which are two smaller 



