﻿136 OPHIOCNIDA SCABRIUSCULA. 



point ; lengtli to breadth, .9 : .7. Side mouth-shields small, slender, not 

 meeting within. Under arm-plates squarish, separated by a narrow 

 line, broader without than within, inner side slightly curved, outer side 

 nearly straight, lateral sides re-enteringly curved, outer corners project- 

 ing ; length to breadth (tenth plate), .4 : .6. Upper arm-plates covering 

 whole upper surface of arm, much broader than long, a little overlap- 

 ping ; outer side with a slight re-entering curve in the middle, lateral 

 sides cleanly rounded; length to breadth (twelfth plate), .4 : 1.5. Spines 

 of the disk minute, somewhat larger and more plenty near the edge of 

 the disk, and smaller and fewer towards the centre and in the inter- 

 brachial spaces below ; the largest are only about .1""° in length ; disk- 

 scales in the centre, and in the interbrachial spaces below, hidden by 

 epidermis ; towards the margin they appear rather stout. Radial 

 shields elongated oval, blunt at both ends, touching each other at their 

 outer tips, and then suddenly diverging, the sj^ace between them being 

 filled by a group of small scales ; length to breadth, 1.6 : .6. Arm-spines 

 three, blunt, rather stout, flattened, hardly tapering, of nearly equal 

 size ; lengths to that of under arm-plate (eleventh joint), .6 : .4. Tenta- 

 cle-scales two, small, but rather thick, standing at right angles to each 

 other, the one lying along the lateral side of the under arm-plate shorter 

 than its neighbor. Color, in alcohol : above, disk, near edges, pale 

 greenish, with a central patch and five radiating lines of yellowish 

 brown (yellow ochre) ; arms also yellowish-brown, but browner than 

 the tint on the disk ; below, coloration the same, without any pale 

 green. Liitken gives the color as pale yellow, with some green bars 

 on the arms. 



This species is distinguished from 0. hisjnda by shorter arms, and 

 shorter spines on the disk. 



LIST OF SPECIMENS. 



Museum of Comparative Zooloyy. 



West Indies. I I University Museum, 



Copenhagen. 



