NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK, 101 



except at base of arm; each plate carries three long, very slender, 

 acicular spines, of which uppermost is longest, equaling one and a 

 half joints, or at base of arm, exceeding two joints. Oral tentacle 

 pore large, opening into mouth slit, protected by six to eight scales on 

 each side; first three basal pores of arm, similar, though there may 

 not be quite so many tentacle scales ; fourth pore with only three or 

 four scales; succeeding pores with a single small scale, though there 

 may be two on fifth and sixth pores. Color (dried from alcohol), 

 grayish, yellowish, or nearly white. 



Localities. — Albatross station 3704, off Honshu Island, Japan, 94 

 to 150 fathoms, fine volcanic sand, 3 specimens; station 4906, 

 Eastern Sea, lat. 31° 39' N.; long. 129° 20' 30" E., 369 to 406 fath- 

 oms, gray globigerina ooze, bottom temperature 43.4°, 3 specimens; 

 station 4907, Eastern Sea, lat. 31° 39' 30" N.; long. 129° 24' E., 406 

 fathoms, gray globigerina ooze, bottom temperature 42.6°, 5 speci- 

 mens; station 4909, Eastern vSea, lat. 31° 38' 30" N.; long. 129° 27' 

 30" E., 434 fathoms, gray globigerina ooze, bottom temperature 42.9°, 

 1 specimen; station 4912, Eastern Sea, lat. 31° 39' 40" N.; long. 129° 

 20' E., 391 fathoms, gray globigerina ooze, bottom temperature 41.9°, 

 5 specimens; station 4913, Eastern Sea, lat. 31° 39' 10" N.; long. 

 129° 22' 30" E., 391 fathoms, gray globigerina ooze, bottom tempera- 

 ture 41.9°, 5 specimens; station 4915, Eastern wSea, lat. 31° 3' N.; 

 long. 129° 25' 30" E., 427 fathoms, gray globigerina ooze, broken 

 shells, bottom temperature 41.9°, 39 specimens; station 4919, 

 Eastern Sea, lat. 30° 34' N.; long. 129° 19' 30" E., 440 fathoms, 

 globigerina ooze, bottom temperature 41.8°, 1 specimen; station 

 4965, off Eastern Japan, lat. 33° 35' 20" N.; long. 135° 10' 50" E., 

 191 fathoms, dark green-gray sand, shells, bottom temperature 49.4°, 

 28 specimens; station 4972, off Eastern Japan, lat. 33° 25' 45" N.; 

 long. 135° 33' E., 440 fathoms, brown-green mud, foraminifera, 

 bottom temperature 39.8°, 3 specimens; station 4980, off East- 

 ern Japan, lat. 34° 9' N.;long. 137° 55' E., 507 fathoms, brown 

 mud, fine sand, foraminifera, bottom temperature 39°, 1 specimen; 

 station 5086, Sagami Bay, lat. 35° 8' 15" N.; long. 139° 20' E., 292 

 fathoms, green mud, coarse, black sand, bottom temperature 43.7°, 37 

 specimens; station 5087, Sagami Bay, lat. 35° 9' 40" N.; long. 139° 

 19' 5" E., 614 fathoms, green mud, bottom temperature 37.5°, 1 

 specimen. Bathymetrical range, 94 to 614 fathoms. Temperature 

 range, 49.4° to 37.5°. One hundred and tliirty-two specimens. 



Type.—Csit. No. 25719, U.S.N.M., from station 4972. 



This species is so easily recognized by the peculiar upper arm plates, 

 that it is not likely to be confused with any other. The smallest 

 specimens have the disk only 5 mm. across, but they show very little 

 difference from the adults save in the greater prominence of their arm 

 combs, a peculiarity referred to above. 



