70 BULLETIN OF THE 



at the apex a vertical tuft of small, smooth, short, spine-like papillae. From 

 near mouth to margin of disk the arms grow wider, but begin to taper from 

 that point. They are cleanly arched above, but flat on the lower surface, a 

 large portion of which is occupied by the deep, oblong, transverse pits (the 

 largest 3.5 mm. long) on whose inner side stand the tentacles, so that this 

 surface presents the appearance of a central, narrow, radiating strip, on whose 

 sides are the tentacle-pits, arranged like the feathers of an arrow. This 

 central strip has a very fine granulation, nearly obscured by skin ; but the 

 lateral region is quite smooth. The sides and upper surface are covered by 

 a coat of soldered grains, about 2 in the length of 1 mm. Among them 

 appeal' numerous small, smooth, slightly sunken, rounded, dark plates, usually 

 1.5 mm. in diameter ; these begin near the tip, with a single plate on the 

 upper surface of each joint, and gradually increase in number towards the 

 base of the arm. The terminal twigs are encircled by double belts of hook- 

 bearing grains (Fig. 486), but the intervening spaces are not yet granulated. 

 Disk thick, rising well above arms ; covered above by a soldered granulation 

 similar to that of the arm, with scattered smooth plates, which sometimes 

 are raised and sometimes sunken. Interbrachial spaces below covered by 

 a minute granulation, which is more or less obscured by skin, and seems 

 smooth to the naked eye. Radial shields not externally indicated. Genital 

 openings very large, extending from opposite the second tentacle-pit nearly, 

 to margin of disk, and capable of great distention ; one of them was open to 

 the width of 9 mm. The mouth-tentacles and first pair on the arm have no 

 tentacle-scales ; thence to margin of disk there are two or three, minute and 

 peg-like, to each tentacle ; for some distance beyond the margin each tentacle 

 has five small, thick, short, wide scales, about 1.5 mm. long, arranged in a 

 single line. Color in alcohol, uniform yellowish brown, with chocolate patches 

 where the smooth plates are. 



Station 192, 129 fathoms, 1 specimen. 



The single specimen had lost one arm and a piece of the disk, the result 

 apparently of an injury, and not of self-division. 



There was sent me recently a single Ophiuran of this Expedition, which has 

 most singular arm-spines, like round-headed nails, or long-handled parasols. 

 They are arranged, not in one, but in several rows, thus forming an exception 

 to all other genera in the group. There is a similar species, but of quite a difl'er- 

 ent genus, in the collection of the second " Blake " Expedition ; and I propose 

 to prepare on these a separate paper. 



