OPHIUROIDEA OF THE BAHAMA EXPEDITION. 45 



together and all arise from the buccal plate; one stout termin- 

 al tooth-papilla. The oral shield is nearly as figured, but 

 the outer end is a little more prominent and the sides are a 

 little incurved at the genital slit; the inner sides are also a lit- 

 tle more incurved. The adoral plates are thickened and 

 lunate, nearly as large at the oral shields. All these shields 

 form together a rhombic figure and with the small . concave 

 first arm-plate they form a raised pantagon around the mouth. 

 The tentacle-scale is more acute than figured, and has longer 

 thorns, which are divergent like branches; distally it becomes 

 slender and delicate, with few very acute branches. The 

 arm-spines are very slender and very thorny, about ten in a 

 row; they are so numerous and crowded as to conceal the 

 arms above. The rows are closely approximate above, on 

 six or more joints, and tubercles at the bases of the upper 

 ones in opposite rows touch on the median line on the first 

 two joints. The spine-ridges are so thick and prominent that 

 they give a beaded appearance to the arm. Upper arm-plates 

 are very small, quadrant-shaped, and widely separated. Un- 

 der arm-plates are not just as figured; they are narrow, rather 

 oblong, scarcely "shield-shaped" for the inner end is nearly 

 truncate or slightly convex, without a distinct angle, and the 

 outer end has a central lobe or prominence, which is a little 

 roughened at the margin. The second plate differs from the 

 rest; it is transversely lozenge-shaped, broader than long, 

 but has the outer median lobe. 



Diameter of disk, 5 to 6 mm. 



Station 13, off Havana, 200 fathoms, five examples. Tak- 

 en in various localities in the West Indies by the Blake Exp., 

 in 73 to 262 fathoms. 



Ophiacantha stellata Lyman. 



Ophiacantha stellata Eyman, 111. Cat. Mus. Comp. Zool., VIII, Pt. II, 

 p. 11, pi. II, figs. 16-18, 1875; Ophiuroidea, V, p. 199, 1882; Bull. 

 Mus. Comp. Zool., X, p. 262, 1883. 



Sta. 13, off Havana, 200 fathoms, one example. 



