138 



BULLETIN 75, UNITED STATES NATIONAL MUSEUM. 



Locality. — Albatross station 4937, Kagoshima Gulf, lat. 31° 13' N.; 

 long. 130° 43' 10" E., 58 fathoms, mud, lava, pebbles, bottom tem- 

 perature 64.8, 1 specimen. 



Type.— Cat. No. 25610, U.S.N.M., from station 4937. 



This specimen is so small and so obviously joung, it is a great pity- 

 to have to give it a name, but it clearly does not belong with any of 

 the other species of Ophiactis in the collection, for the oral shields, 

 adoral plates, oral papillge, arm plates and spines are all more or 

 less distinctive. I can not find any previously known species to 

 which I can refer it and I have therefore decided to call it dyscrita. 



OPHIACTIS BRACHYASPIS, new species.o 



Disk 3 mm. in diameter; arms about 15 mm. .long. Disk covered by 

 about one hundred and seventy-five irregular scales, without spinelets. 

 Radial shields short, though longer than wide, well separated within 

 but touching distally. Arms six, not ver}^ attenuate. Upper arm 



Fig. 53.— Ophiactis brachyaspis. x 16. a, fkom above; 6, from below; c, side view of three 



ARM .joints near DISK. 



plates elliptical, much wider than long, broadly in contact far out 

 on arm. Interbrachial spaces below covered with scales. Genital 

 slits very inconspicuous. Oral shields rounded pentagonal, much 

 wider than long. Adoral plates short and broad but meeting in 

 midradial line. Oral papillae single, one on each jaw margin, flat and 

 wide. First under arm plate, apparently concealed by meeting of 

 adoral plates; second plate (seemingly first) large, squarish or broadly 

 hexagonal; succeeding plates somewhat longer than wide, almost if 

 not quite, broadly in contact. Side arm plates moderate, not meet- 

 ing above or below on basal half of arm, each with four short, thick 

 arm spines, of which the middle pair are longest and about equal the 



a Bpaxbg, signifying short, and aancg, signifying shield, in reference to the short 

 radial shields. 



