OPHIURANS OF THE PHILIPPINE AND ADJACENT WATERS. 169 



Affinities and distinctive features. — Amphiodia debita is distin- 

 guished from all the other species of Amphiodia with two tentacle 

 scales and three arm spines by the unusual dimensions of the inner 

 tentacle scale. It possibly approaches A. brocki (Doderlein) which 

 has, like itself, three equal mouth papillae, but the adoral plates are 

 not in contact in the interradial median line, the under arm plates 

 are as long as broad Avith the distal border convex, and, although 

 the two tentacle scales are rather large, the dimensions of the internal 

 scale are inferior to those which we see in A. debita. 



In its three almost equal arm spines, in the form of the mouth 

 shields, and in the size of the tentacle scales, the new species recalls 

 ^4. grata (Kcehler) of the Siboga expedition, which is an abyssal 

 species; but this latter possesses numerous arm spines and the upper 

 and under arm plates are of an entirely different form. 



A. debita approaches .4. lutkeni (Ljungman) ; that species is espe- 

 cially characterized by the presence at the border of the disk of 

 little spines, a character which we can not determine here, as the 

 disk is torn off, but the internal tentacle scale is shorter, the arm 

 spines are very much thicker, and the mouth papillae are more elon- 

 gated. It is evidently a very different species. Amphiodia debita 

 also can not be confused with A. occidentalis (Lyman) from Cali- 

 fornia, in which the mouth shields have a different form, or A. ochro- 

 leuca (Brock), in which the tentacle scales are moderately developed, 

 but in which the mouth shields and the upper and under arm plates 

 have a different form, and in which the mouth papillae are unequal. 

 Amphiodia urtica (Lyman) recalls our species in its mouth plates, 

 but its tentacle scales are very small. 



AMPHIOPLUS LEGATUS, new species. 



Plate 67, figs. 1-3 ; plate 96, fig. 9. 



Locality. — Albatross station 5119; Balayan Bay and Verde Island 

 Passage; Sombrero Island bearing S. 80° E., 35.03 kilometers (18.9 

 miles) distant (lat. 13° 45' 05" N., long. 120° 30' 30" E.) ; 721 meters 

 (394 fathoms) ; January 21, 1908; gn. M., S. 



One specimen (Cat. No. 41179, U.S.N.M.). 



Description. — The diameter of the disk is 10 mm. ; four arms are 

 broken off at a short distance from the base, and the fifth is pre- 

 served for a length of 150 mm. The jar contains in addition two 

 fragments of arms, of which one exceeds 40 mm. ; the arms therefore 

 must be fairly long. 



The disk is rounded, a little depressed in the middle of the inter- 

 radial spaces, and slightly excavated above the insertions of the 

 arms ; it is rather thick. The two surfaces are plane, and the borders 

 are very rounded. 



