120 



BULLETIN 75, "LTNITED STATES NATIONAL MUSEUM. 



in a very narrow, oblique, oval area. Genital slits large, but genital 

 scales rather slender and inconspicuous. First under arm plate very 

 small, but succeeding plates large and somewhat hexagonal, scarcely 

 in contact, about as long as wide. Side arm plates rather large, each 

 one carrying a vertical spine-ridge upon which are borne six to eight 

 rather slender, bluntly pointed arm spines; uppermost spine longest, 

 about equal to three arm joints, lower ones successively shorter. 

 Tentacle pores moderately large, each with a single blunt tentacle 



Fig. 45.— Ophiopholis longispina. X5. a, from above; 6, from below; c, side view of two arm 



JOINTS NEAR DISK. 



scale. Color (dried from alcohol), deep pink, marked with lighter; 

 pale pink becoming almost white; or light yellowish brown. 



Localities. —Albatross station 2890, off Oregon, lat. 43° 46' N.; 

 long. 124° 57' W., 277 fathoms, gray sand, bottom temperature 42.2°, 

 3 specimens; station 3070, off Washington, lat. 47° 29' 30" N.; long. 

 125° 43' W., 636 fathoms, green mud, bottom temperature 37.9°, 

 43 specimens; station 3071, off Washington, lat. 47° 29' N.; long. 

 125° 33' 30" W., 685 fathoms, green mud, bottom temperature 38°, 

 3 specimens; station 3104, off California, lat. 37° 23' N.; long. 123° 8' 



