70 BULLETIN 84, UNITED STATES NATIONAL MUSEUM. 



radius. The radial sliields are narrow, elongated, almost four times longer tlian 

 wide, with a convex internal side and a sharply pointed proximal apex. Their 

 length is inferior to half the radius of the disk; distally, the}' are contiguous on 

 about one-tliii-d of their length, and, proximally, they are separated by a few rows 

 of plates, but they are not very divergent. 



The under face of the disk is covered all over with very thin, imbricated, and 

 equal plates, wliich uninterruptedly succeed those of the upper face. The genital 

 slits are narrow. 



Tlie mouth sliields are lozenge-shaped and longer than mdc, with four equal 

 sides and rounded angles, especially the lateral angles, wliich are very obtuse. The 

 adoral plates, of middhng size, are triangular, with three more or less concave sides; 

 they are widened outwardly, and one can see a thin blade which separates the mouth 

 shield from the fii'st lateral braclual plate. The oral plates are low. The oral 

 papillae, amounting to three, are subequal, short, rather thick with a blunt point; 

 the internal papUla, however, is a little more elongated than the other two. 



One can scarcely distinguish on the middle of the upper face of tlie arms 

 the dark longitudinal line Indicated by Ljungman. The dorsal plates are large 

 and extremely wide, at least three times wider than long, with an almost straight 

 proximal side, a wider distal side, wliich is sometimes a little depressed in its middle, 

 and strongly rounded lateral sides joining the two other sides by angles which 

 are also rounded. These plates are sometimes split into two lateral halves by a 

 furrow near their middle, and sometimes the number of pieces is even larger, owing 

 to there being two or three h-regular furrows. All these plates are contiguous. 



The fii'st under braclual plate is fairly long, triangular, with a truncated proximal 

 angle and a strongly convex distal side. The succeecUng ones are pentagonal, 

 much wider than long, with a very obtuse and rounded proximal angle, and straight 

 sides wliich meet by rounded angles. 



The lateral plates are little protruding. They carry three fairly wide, flattened 

 slightly lanceolate spines, the point of wliich is obtuse and rough; these spines are 

 about the same length and they equal the article. 



The tentacular scales, two in number, are subequal and rather large; the exter- 

 nal scale, supported by the lateral bracliial plate, is rounded; the internal one, which 

 is inserted on the ventral plate, is more elongated. 



A. luilceni has been classified by Ljungman in the genus AmphiphoUs wliich, 

 according to Idni, included such species as have three oral papillse on each side, the 

 external papilla being either wider or narrower than tlie other two. As, in 

 A. luikeni, the three papiUas are subequal, tliis species must be placed in the section 

 Amphiodia of Verrill. 



AMPHIODIA (=AMPHrtrRA) PULCHELLA (Lyman). 



AmpMura pulchella Lyman (69), p. 337. 

 Amphiura pulchella Ljungman (71), p. 648. 

 Amphiura pulchella Lyman (75), pL 5, fig. 75. 

 Amphiura pulchella Lyman (82), pp. 125 and 147. 

 Amphiodia pulchella H. L. Claek (01), p. 248. 



Albatross station 2765. Jan. 12, 1885. Lat. 36° 4.3' S.; long. 56° 2.3' W.; 

 10.5 fathoms; s. brk. sh. Five specimens. 



