144 



BULLETIN 75, UNITED STATES NATIONAL MUSEUM. 



Interbrachial spaces below naked. Genital slits rather large. Oral 

 shields nearly elliptical, much wider than long. Adoral plates 

 roughly triangular, with the side next the oral shield deeply concave, 

 not meeting either radially or interradially. Oral papilla? two on a 

 side, one large and conspicuous at apex of jaw, one minute and scale- 

 like at outer corner of mouth angle; first oral tentacle scale conspicu- 

 ous and giving the impression of being a third oral papilla. First 

 under arm plate small, tetragonal or pentagonal; succeeding plates 

 much larger, somewhat pentagonal, with a proximal angle, rather 

 longer than wide, scarcely in contact. Side arm plates rather small, 

 barely meeting, above and below, on basal part of arm; each plate 

 carries three subequal spines, about as long as the arm joint. Ten- 

 tacle pores very large, but tentacle scales single and small. Color 

 (dried from alcohol), grayish. 

 Locality.— Albatross station 4781, Bering Sea, lat. 52° 14' 30" N.; 



Fig. 57.— Amphiura euopla. a-c, X 5; d, young, X 10. o, from above; 6, from below; c, side view 

 OF three arm joints near disk; d, side view of two arm joints from a young specimen. 



long. 174° 13' E., 4S2 fathoms, fine gray sand, pebbles, bottom tem- 

 perature 38.6°, 1 specimen. 



Type.— Cat. No. 25627, U.S.N.M., from station 4781. 



This specimen does not seem to be referable to any known amphiu- 

 roid and I have accordingly thought best to give it a name. The 

 naked interbrachial spaces, the three arm spines, the peculiar oral 

 papillae, and the single tentacle scale combine with the characteristic 

 oral shields, adoral plates, and upper arm plates to give the species a 

 unique appearance. 



AMPHIURA EUOPLA, new species.a 



Disk 10 mm. in diameter; arms about 80 mm. long. Disk covered 

 by numerous (500 to 600) small scales, the largest of which are around 

 the radial shields. Radial shields about twice as long as broad, more 



« EuonXog, signifying well-armed, in reference to the numerous, rather crowded arm 

 spines. 



