OPHIURANS OF THE PHILIPPINE AND ADJACENT WATERS. 227 



size and width of the radial shields, as well as by the form of the 

 upper arm plates in which the broadest part is close to the distal 

 border, and by the dorsal surface of the disk which is entirely without 

 spines and only shows small granules. The coloration is also different. 

 In the development of the radial shields 0. deceptor recalls more espe- 

 cially 0. fallax, but it is distinguished from that species by having 

 the under arm plates longer and the radial and interradial spaces of 

 the dorsal surface of the disk more reduced, by the absence of spines 

 on the dorsal surface of the disk, by having the ventral surface of the 

 disk furnished with very small, though evident, plates, and by the 

 form of the upper arm plates of which the maximum width is close 

 to the distal border, while according to de Loriol's figures this maxi- 

 mum occurs towards the middle of the plate in O. fallax. It is dis- 

 tinguished from 0. purpurea, which has, like itself, large radial 

 shields, by the very different coloration, by the absence of spines on 

 the disk, and by having the upper and under arm plates longer than 

 broad. 



OPHIOTHRIX ELEGANS Lutken. 



Plate 56, figs. 1-3. 

 See for bibliography : 

 Ophiothrix elegans K<ehlee ('04a), p. 110, fig. — H. L. Clark ('15), p. 271. 



Locality. — Albatross station 5179 ; Romblon Light bearing S. 56° 

 E., 8.34 kilometers (4.5 miles) distant (lat. 12° 38' 15" N., long. 122° 

 12' 30" E.) ; 67 meters (37 fathoms) ; March 25, 1908, hrd. S. 



One specimen (Cat. No. 41014, U.S.N.M.). 



Notes. — I have thought it best to refer to Ophiothrix elegans a 

 specimen of small size of which the color pattern forcibly recalls 

 Liitken's description. The diameter of the disk is 5 mm., and the 

 arms are scarcely 20 mm. long. The dorsal surface of the disk is uni- 

 formly covered with small club spines ending in three or four fine, 

 divergent, subequal, and rather elongated spinules. These club spines 

 occur also on the radial shields, but they are there less closely 

 crowded. They elongate somewhat toward the borders of the disk, 

 and become longer on the ventral surface, which they cover in large 

 part ; they are always terminated by three or four elongated spinules. 

 The outlines of the upper and under arm plates, as well as those of 

 the mouth plates, the arm spines, etc., show well all the characters 

 which I described in O. elegans in 1904 from the type specimen in 

 the Copenhagen Museum ('04a, p. 110). I may notice only that the 

 distal border of the under arm plates is a little more rounded. 



The general color is pinkish gray on the dorsal surface. A dark- 

 brownish purple band runs all along the median line of the arms 

 and extends to the neighborhood of the center of the disk. This 



