NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK. 159 



not distinguishable by any constant characters from the same parts 

 in the preceding species (macraspis). The distal oral papillae are 

 often distinctly pointed, the oral shields are sometimes as long as wide, 

 and the number of arm spines is commonly four, though always five at 

 base of arm, but never six, so far as I can see even in the largest 

 specimen. C :>lor (dried from alcohol), disk, gray or brownish; arms, 

 very pale brownish, or yellowish or nearly white. 



Localities. Albatross station 3227, Bering Sea, lat. 54 36' 30" N.; 

 long. 166 54' W., 225 fathoms, green mud, bottom temperature 38.6, 

 72 specimens; station 3478, off California, lat. 36 44' 45" N.; long. 

 120 57' W., 68 fathoms, gray sand, mud, 3 specimens and a mass of 

 arms; station 4862, off Korea, lat. 36 20' N.; long. 129 50' E., 184 

 fathoms, green mud, bottom temperature 32.9, 1 specimen; station 

 4863, off Korea, lat. 36 21' N.; long. 129 53' E., 250 fathoms, green 

 mud, bottom temperature 32.7, 1 specimen; station 4997, Gulf of 

 Tartary, lat. 47 38' 40" N. ; long. 141 24' 30" E., 318 fathoms, green 

 mud, bottom temperature 32.8, 2 specimens; station 5066, Suruga 



FIG. (17. AMPHIODIA EUEYASPIS. X 4. a, FROM AnovE; 6, FROM BELOW; c, SIDE VIEW OF THREE ARM 



JOINTS NEAR DISK. 



Gulf, lat. 35 6' 5" N. ; long. 138 40' 20" E., 211 to 293 fathoms, fine 

 black sand, bottom temperature 50.8, 1 specimen; Iliuliuk, Unalaska, 

 1 specimen; Bering Sea, 5 specimens. Bathymetrical range, 68 to 

 318 fathoms. Temperature range, 58 to 32.7. Eighty-six speci- 

 mens. 



Type. Cat. No. 25652, U.S.N.M., from station 3478. 



It is only after great hesitation that I have determined to keep this 

 species separate from the preceding. The differences in the scaling 

 of the disk and in the form of the radial shields are obvious and seem 

 to be remarkably constant, so that there is no difficulty in deciding to 

 which species a given specimen belongs. Yet it is difficult to find any 

 other character, which is at all reliable, by which the two forms can 

 be distinguished. As they were seldom both taken at the same sta- 

 tion, thus indicating preference for somewhat different habitats, my 

 impression of their distinctness is confirmed. The largest specimen 

 of euryaspis measures 16 mm. across the disk. One of the specimen- 

 from 3227 has six arms. 



