OPHIUROIDEA OF THE BAHAMA EXPEDITION. 49 



separated. The first one is small and deeply concave, or 

 sheath-like, with two inner, vertical, flat crests. Tentacle- 

 scales flat, ovate, of moderate size; on the first three or four 

 joints there are, in large specimens, usually two; on the rest 

 only one. The proximal tentacle-pores are not very distinct- 

 ly larger than the rest. 



Arm-spines unequal, rather long, scarcely translucent; the 

 dorsal ones are not approximate in the basal rows; the upper 

 spines on the basal joints are mostly long, rather slender, 

 flat, tapered, subacute, roughened by minute, close denticles 

 along each edge. Those lower down become a little shorter, 

 stouter, and flatter, and are mostly somewhat bent, obtuse at 

 tips, and with sharply serrulate edges. (See figs. 4-5)- 

 There are usually five spines in each row proximaily. 



Color in alcohol, yellowish white. 



Diameter of disk 12 mm; length of longest arm, broken at 

 tip, 65 mm. 



Off Havana, no to 260 fathoms. 



Ophiopristis hirsuta [Lym) . 



Ophiacantha hirsuta Lyman, 111. Cat. Mus. Comp. Zool., VIII, Pt. II, 

 p. 12, pi. II, figs. 21-23, 1875; Bull. Mus. Comp. Zool., V, 9, p. 230; 

 op. cit. X, p. 261; Report Voy. Challenger, Zool., Ophiuroidea, V, 

 p. 198, 1882. 



The specimens in the collection differ considerably from 

 Mr. Lyman's figures. In all, the spinules of the disk are 

 much more numerous than figured. In some they are most- 

 ly very long and slender, as figured; in others they are much 

 shorter, but slender and sharp. The radial shields are cov- 

 ered by the small scales and spines, except near their ends, 

 which are sometimes in contact and sometimes separated by 

 a few rows of minute scales. The under side of the disk is 

 covered by naked, smooth, thin, rounded scales, with few 

 spinules. Oral shields large, round-rhombic, about as long as 

 wide, with a distinct, but small, distal lobe, (not evenly round- 

 ed, as figured); the inner angle is obtusely rounded; the in- 



V— 1 D 



