48 



BULLETIN 75, UNITED STATES NATIONAL MUSEUM. 



wide and conspicuous at their upper, outer ends; marginal row of 

 papillae well developed; seen from above, arm comb consists of six 

 to eight slender well-spaced papilla, succeeded by much broader ones 

 in contact with each other. First under arm plate wider than long, 

 somewhat pointed distally; second plate much larger, nearly as long 

 as wide, somewhat hexagonal; succeeding plates much wider than 

 long, somewhat triangular, rapidl}' becoming very small; only first 

 two or thi-ee in contact. Side arm plates large, meeting below but 

 not above; each plate carries three arm spines, of w^hich lowest is 

 longest and stoutest and exceeds one-half joint; middle arm spine 

 very short and peg-like, not half as long as lowest. Oral tentacle pores 



not opening clearly into mouth 

 slit, with about four scales on 

 each side. First two or three 

 pairs of pores of arm rather 

 large, with two to five (usually 

 three or four) scales on each 

 side ; succeeding pores small or 

 wanting, with only a single ten- 

 tacle scale, but that seems to 

 persist to end of arm. Color 

 (dried from alcohol), dull pur- 

 plish-gray above, creamy- 

 whitish below; in some speci- 

 mens the arms show indications 

 of being banded with darker. 

 Localities. — Albatross station 

 4900, off Goto Islands, Japan, 

 lat. 32° 28' 50'' N.; long. 128° 

 34' 40" E., 139 fathoms, gray 

 sand, broken shells, bottom 

 temperature 52 . 9 ° , 2 specimens ; 

 station 4933, off Kagoshima 

 Gulf, Japan, lat. 30° 59' N.; 

 long. 130° 29' 50" E., 152 fathoms, rocky, bottom temperature 56°, 

 1 specimen; station 5091, in Uraga Gulf, Japan, lat. 35° 4' 10" N.; 

 long. 139° 38' 12" E., 197 fathoms, green mud, coarse black sand, 

 pebbles, bottom temperature 47.6°, 2 specimens. Bathymetrical 

 range, 139 to 197 fathoms. Temperature range, 56°-47.6°. Five 

 specimens. 



Type.— Cat. No. 25535, U.S.N.M., from station 5091. 



Although this species is nearly related to sarsii and Mnhergi, it is 



easily distinguished from either by the very peculiar, short, peg-like 



middle arm spine. The size and proportions of the arm spines show 



some diversity in the different specimens, but in every case the middle 



FiG.lO.— Ophiuramiceacantha. Xi. a, from above; 

 b, FROM below; c, side view of two arm joints 



NEAR DISK. 



