﻿OPPIIOCOMA PICA. 



91 



spaces dark brown, varied with yellowish ; 3'ellowish spots between the 

 under arm-plates. 



Variations. — The arrangement of colors on the disk varies ; some- 

 times the disk is wholly dark, or, again, only spotted with light yel- 

 lowish ; but the arms are always more or less banded with light. A 

 light mark on each side of the mouth-shield is very characteristic. 

 A young specimen, with a disk of 9"™-, had arms 34""°- long ; there 

 were five arm-spines. Another had four, and close to the disk five 

 arm-spines ; the disk was to the arms as 6 : 21. In younger specimens 

 the tooth-papillEe are of course fewer. 



Miiller & Troschel made the singular mistake of describing this 

 strongly marked species under two names, 0. pica and 0. Uneolata. 

 Both descriptions are inaccurate ; so much so that I described it under 

 a third name, O. sannio. A glance at the originals in the Jardin des 

 Plantes and the Berlin Museum, was enough to remove all error. The 

 originals of 0. pica, in Paris, are dried, and about half grown. Disk, 

 15°""- ; arm, 50°"'- ; five arm-spines, of which the upper is 3.2°'"' long. 

 The original of 0. Uneolata (Berlin Zool. Mus., No. 951) is also not 

 quite fuUy grown. The disk is IS""' in diameter ; arm, 58""°- long ; 

 five rows of spines, whereof the upper and middle ones are longest. 

 The specimens are dried, and are from Aden on the Red Sea. 



LIST OF SPECIMENS. 



WheDce obtained. 



Musemn of Comparative Zoology, 



12+ 



Sandwich Islands. 



Sandwich Islands. 



Sandwich Islands. 



Kingsmills Islands. 



Sandwich Islands. 



Java. 



Society Islands. 



A. Garrett. 



A. Garrett. 



A. Garrett. 



A. Garrett. 



A. Garrett. 



Jardin des Plantes. 



A. Garrett. 



Dried. 

 Alcoholic 



