﻿160 



OPHIOTHRIX MAGNIFICA. 



shields much obscured by surrounding spines, but bearing only a few 

 small spines themselves ; length to breadth, 3.5 : 1.7. Arm-spines stout, 

 rather blunt, rounded, slightly and regularly tapering, deeply corru- 

 gated lengthwise, bearing many small, blunt thorns ; upper spines 

 scarcely flattened at all j second and third spines usually longest and 

 stoutest ; eleventh joint, eight spines ; lengths to that of under arm- 

 plate, 2.4, 2.6, 3.1, 2.1, 2.1, 1.5, .9, .5 : .7. Tentacle-scales distinct, flat, 

 rounded at their outer end. Color, in alcohol : above, disk dull indigo- 

 blue (cobalt and indigo-blue) ; arms the same, but banded with lighter ; 

 usually two or three joints to each band ; arm-spines faint blue ; below, 

 interbrachial spaces a little lighter than upper surface ; imder arm-plates 

 variegated with cross lines and specks of white, and of darker and 

 lighter blue, giving the arm a banded appearance. 



Variations. — The general color may incline more to greenish-blue, 

 or, on the other hand, to purplish-blue ; and the marking of the under 

 arm-plates may form more or less distinct bands. The largest specimen 

 had the disk 14"""- in diameter, and some of the spines on the disk as 

 long as S.l""'. Many of the arm-spines were tipped with white. 



This very beautiful Oj^hiothrix belongs to the group which has only 

 long spmes on the back of the disk ; it differs from 0. Orstedii in 

 greater stoutness and shortness of the disk-spines, and in more cylin- 

 drical arm-spines ; it has more and shorter spines than 0. Suensonii, 

 and is larger than either of these species. 



LIST OF SPECIMENS. 



Whence obtained. 



Museum of Comparative Zoology. 

 150 I 1043 I 1 I Peru. | | BIr. Raj-mond. | Alcoholic 



Smithsonian Institution. 

 1043 I .. I I Peru. I 1 Mr. Raymond. I Alcoholic, 



