NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK. 131 



40 specimens; Unalaska, 4 specimens; Kyska, 9 to 12 fathoms, 62 

 specimens; Port Levasheff, Unalaska, 20 to 30 fathoms, 1 specimen; 

 Port Etches, Alaska, 5 specimens; Constantino Harbor, 15 specimens; 

 Unga, 3 specimens; Agattu, 46 specimens; Iliuliuk, 64 specimens; 

 Port Al thorp, Alaska, 1 specimen; Chineak Bay, Kadiak, 1 specimen; 

 Meclui Island, 2 specimens; Aleutian Islands, 2 specimens; Bering 

 Island, 19 specimens; Shumagin Islands, 1 specimen; Dolgoi Sound, 

 30 fathoms, 1 specimen; Bay of Islands, 8 specimens; Avatscha 

 Bay, Kamtchatka, 1 specimen; 10 miles west of Point Franklin, 

 Alaska, 13^ fathoms, sand, 21 specimens; between Icy Cape and 

 Cape Lisburne, Alaska, 7 specimens; lat. 53 11' N. ; long. 166 51' W. 

 84 fathoms, black sand, pebbles, bottom temperature 40.6, 8 speci- 

 mens; Bering Straits, 2 specimens; Sitka, 1 specimen; Alaska, 134 

 specimens; Arctic Ocean, 1 specimen; AWatrossTLydTogr&pbic station 

 1141, off Alaska, 84 fathoms, 8 specimens. Bathymetric range, 9 

 to 372 fathoms. Temperature range, 51.4 to 29.8. One thousand 

 six hundred and forty-three specimens. 

 These specimens vary greatly in the 

 disk covering, ranging all the way from 

 those with numerous disk plates sepa- 

 rated by lines and bands of nearly 

 spherical granules to those in which 

 the disk is largely covered by coarse 

 spines, and only one or two plates can 

 be distinguished. Many of the speci- 

 mens so grade into japonica that sep- 

 aration from that variety is difficult 

 and arbitrary. As a rule, the supple- FIG. 43. OPHIOPHOLIS ACULEATA. xs. 



i i FROM ABOVE. 



mentary upper arm plates are much 



coarser and more angular than in japonica (compare fig. 48 with fig. 

 476), and this peculiarity is very noticeable when these Alaskan speci- 

 mens are compared with some from the coast of Maine. The majority 

 of the Alaskan specimens have relatively few large supplementary 

 plates, as in fig. 48, while the Maine specimens have numerous small 

 ones ; in the Alaskan specimens, too, the disk is commonly more or less 

 spiny, while I have never seen spiny specimens from the Atlantic. The 

 Albatross collections leave no doubt that in Opniopholis aculeata, as in 

 Ophiura sarsii anil 0. nodosa, we have a species of circumpolar distri- 

 bution extending far to the south in both the Atlantic and Pacific 

 oceans. The specimens here recorded from off Washington, Oregon, 

 and California are all small and obviously young. They would probably 

 be more properly regarded as var. Jcennerlyi, but as they are too young 

 to show definite characters, it has seemed best to record them simply 

 as aculeata One of the specimens from Captains Harbor is remark- 



