316 RECENT OPHIURANS. 



The arms are nearly three times the disk diameter (instead of about twice as in 

 stuwitzii) and are very slender distally, the joints becoming cylindrical, more 

 than twice as long as thick (hence the name) and quite smooth. The arm-spines 

 are 4 or 5 at the base of the arm, slender, bluntly pointed and well-spaced; 

 they are quite different from the minute flattened tentacle-scales; in stuwitzii, 

 the arm-spines are often 6 in number, and are flattened and rather crowded, 

 and the tentacle-scales are large and resemble the lower arm-spines. The median 

 ridge on the lower arm-plates is confined to 5 or 6 basal joints in macrarthra. 

 Color (dried from alcohol), white. 



HoLOTYPE (M. C. Z. 757). Off Georgia, 233 fms. Blake St. cccxxi; 

 lat. 32° 43' 25" N., long. 77° 20' 30" W. 



This specimen is labeled by Mr. Lyman: "Ophioglypha stuwitzii? var. 

 Arm spines slenderer and more spaced than in smaller specimens of true stuwitzii, 

 and back scales thinner. About as in 2 vars. of O. sarsii." Mr. Lyman does 

 not seem to have noticed the difference in the terminal half of the arm which 

 clearly separates this species from stuwitzii. It seems to me from Koehler's 

 description and figure (1914. Bull. 84 U. S. N. M., p. 16, pi. 3, f. 5) that the 

 ophiuran from Albatross St. 2675 which he referred to Lyman's Ophioglypha 

 elevata is a specimen of macrarthra. I do not think these western Atlantic speci- 

 mens should be referred to the Challenger species from Prince Edward Islands, 

 southern Indian Ocean, since the disk-scahng, arm-form, upper and under arm- 

 plates, and tentacle-scales are all different. In elevata so far as can be judged 

 from Lyman's figures, the arms are not at aU compressed, with a faint keel 

 basally, as they are in macrarthra and stuwitzii, and the basal arm-plates are 

 very much larger and relatively wider. 



1182. S. NODOSA (Lutken). 



Ophiura nodosa Ltjtken, 1855. Vid. med. f. 1854, p. 100. 1858. Add. ad hist. Oph., pt. 1, 



p. 48, pi. 2, f. 9a-b. 

 Stegophiura nodosa Matscmoto, 1915. Proe. Acad nat. sci. Phil., 67, p. 79. 



175 specimens. Karahavet. Spitzbergen ' : off Hackluyts Head, 20 fms. 

 Greenland. Labrador: off Caribou, 10-12 fms.; Egg Harbor, 7 fms. Strait 

 of Belle Isle. Alaska: Icy Cape; off Cape Sabine. Bering Sea, 17-20 fms. 

 Bering Strait: 12 miles east of Kings Island, 17 fms. Aleutian Islands: Unga, 

 Coal Station, 8-9 fms. Okhotsk Sea, 25 fms. Saghalin: Aniwa Bay, 42^3 fms. 



1183. S. SCULPTA (Duncan). 



Ophioglypha sculpta Duncan, 1879. Journ. Linn. soc. Zool., 14, p. 455, pi. 9, f. 6-8, pi. 11, f. 35. 

 Stegophiura sculpta Matsumoto, 1915. Proc. Acad. nat. sci. Phil., 67, p. 79. 



' Without definite locality. 



