ie85.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 445 



Ophiacantha bidentata (Eetz.) Ljung. ; Lyuian (^pars) "Challenger" Ophiuroidea. 

 Ophiacantha spinuJosa (M. and Tr.) Lyniau, lUus. Catalogue Mus. Comp. Zo- 

 ology, p. 93, ligs. 6, 7. 



The form here intended is the same as that described and figured by 

 L^ man, Liitken, Duncau and Sladeu, and others as 0. spinulosa, from 

 northern waters. Ljmau's deep-water specimens, in part at least, 

 belong to 0. fraterna. 



Common northward, in moderate depths, from Massachusetts Bay to 

 Greenland. 



Ophiolebes Acanellae Verrill. 



Verrill, Amer. Journ. Sci., vol. sxis, p. 153, February, 1885. 

 Verrill, Report U. S. Fisli Com. for 1883, p. 46, 1885. 



Disk rounded, swollen, covered above and below with rather large, 

 globular or capitate stumps, minutely spinulose at the end. Arms short. 

 Arm-spines at base of arms, six or seven, short, obtuse, rough, with 

 small spinules ; the four lower are shorter and stouter than the upper 

 ones, with a blunt or clavate, rough, thorny tip ; the upper ones are 

 more cylindrical, but mostly blunt, shorter than the breadth of the arm- 

 joint; the lower groups of three or four spines extend nearly to the 

 mouth-angles. Mouth -papillaB, three or four on each side, small, nearly 

 equal, rounded, obtuse. Diameter of disk, 6"™. 



Oft' Nova Scotia, in 91 to 122 fathoms. Station 2071, on Paramuricea 

 borealis, in 113 fathoms. 



Amphiura Otteri Ljuugmauu (?) ; Lymau. 



In this species the disk is covered with small scales, above and below; 

 the radial shields are elongated, wedge-shaped, with a narrow group 

 of scales between their divergent and tapered inner ends. The arms 

 are very long and rather slender, flattened, usually with about six 

 spines, toward the base, but in large specimens there may be as many 

 as eight; they are moderately long, tapered, and, except the upper 

 ones, mostly a little bent toward the end, with the tij) slightly hooked. 

 Two flat, blunt tentacle-scales, which are very small and indistinct in 

 young specimens ; a pair of stout mouth-papillse at the end of each jaw, 

 and a smaller spiniform one on each side, a little farther back ; a stout, 

 erect, spiniform tentacle-papilla at the outer end of the mouth-slit, on 

 each side. 



Oft' Martha's Vineyard in 182, to 1,608 fathoms (487 to 1,008 fathoms, 

 1883). Not uncommon. 



Amphiura fragilis Verrill, sp. uov. 



Verrill, Report U. S. Fish Com. for 1883, p. 47, 1885. 



Disk, five-lobed, covered above with small, delicate scales, naked be- 

 neath; radial shields, i^ear-seed- shaped, slightly divergent, the inner 

 ends separated by a narrow row of scales. Arms long and slender; 



