NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK. 165 



Locality. Albatross station 2866, off Washington, lat. 48 9' N.; 

 long. 125 3' W., 171 fathoms, gray sand, bottom temperature 43.2, 

 8 specimens. 



Type. Cut. No. 25615, U.S.N.M., from station 2866. 



This species bears a curious superficial resemblance to A. macras- 

 pis, but the bare interbrachial spaces, the upper arm plates, and the 

 oral shields are quite unlike those of that species. As only one of 

 the eight specimens possesses a disk, it is impossible to estimate the 

 value of the bare interbrachial spaces; they may prove to be very 

 variable. 



AMPHIODIA PSILOCHORA, new species.o 



Disk 8 mm. in diameter; arms about 65 mm. long. Disk more or 

 less deeply indented in interbrachial areas, covered by a close coat 

 of scales, the largest of which are near the center of disk and close 

 to the radial shields, while the smallest are at the interradial mar- 



FIG. 72. AMPHIODIA PSILOCHOHA. X f>. n, FROM ABOVE; b, FROM BELOW: r, SIDE VIEW OF THREE ARM 



JOINTS NEAR DISK. 



gins. Radial shields long and curved, separate or barely touching 

 distally. Upper arm plates at first somewhat hexagonal, with the 

 proximal side shortest, but soon the angles are rounded off and they 

 become biconvex, much wider than long and scarcely or not at all 

 in contact. Interbrachial spaces below bare. Oral shields some- 

 what variable, wider than long, with a broad proximal angle and a 

 rounded (or sometimes truncate) outer margin. Adoral plates vari- 

 able, nearly triangular, sometimes meeting within, but often well 

 separated. Oral papilla^ three on a side, the first one (at apex of 

 jaw) thick and rounded; the second small, flat, and pointed; the 

 third larger, often longer, and sometimes attenuate pointed. The 

 tentacle scale of first oral pore is often visible between the first and 



a dl>e, signifying bare, and %wpoc, signifying a space, in reference to the naked 

 iuterbrachial spaces. 



