﻿OPIIIOPSILA ARANEA. 



151 



the end ; lengths to that of under arm-plate (thirteenth joint), .5, .4, .4, 

 .4, .5, .8 : .5. Outside tentacle-scale minute, flattened, spiniform ; length of 

 inside scale to that of under arm-plate, 1 : .5. Color, in alcohol : nearly 

 uniform pale brownish-gray, with numerous specks of black pigment on 

 the back and interbrachial spaces of the disk, and on the upper arm- 

 plates ; mouth-parts nearly white, with a black speck on each mouth-shield. 



Variations. — The coloration in alcoholic specimens is nearly uni- 

 form, and the other characters vary little. A specimen with a disk of 

 8"""-, had arms 100""° long. This may be considered an average pro- 

 portion. Almost always the tips of the arms are broken off. The 

 largest specimens have a disk of over 11""°. 



0. Riisei has been found at St. Thomas by Mr. Kiise, but is appar- 

 ently not very common there ; and the same remark is true of the 

 Tortugas Islands, of Key West, and of some other parts of Florida ; but 

 at Cape Florida it has been taken in the greatest abundance. 



LIST OF SPECIMENS. 



995 

 1177 



Museum of Comparative Zoology. 



12+ 



Cape Florida. 



Florida? 



Key West, Fla. 



Florida. 



Cape Florida. 



Florida. 



Apr. 1858. 



Smithsonian Institution. 



\2-\-\ Cape Florida. 

 1 Florida. 



G. Wurdeman. 

 Prof. Afjassiz. 

 J. E. Mills. 

 Prof. Agassiz. 

 G. Wvirderaan. 

 Prof. Agassiz. 



G. Wurdeman. 



Ophiopsila aranea Foebes. 



Ophiopsila aranea Forbes. Trans. Linn. Soc., XIX. p. 149. 

 Ophianoplus marmoreus? Sars. Nyt. Mag. for Naturvid., X. p. 23. 

 Ophiopsila marmorea Lutken. Addit. ad Hist. Oph., p. 136. 



LIST OF SPECIMENS. 



|.. |.. , 



Museum of Comparative Zoology. 

 Altrer. I 1 Jardin des Plantes. I Alcoholic. 



