﻿OPHIACTIS KREBSir. 

 LIST OF SPECIMENS. 



Ill 



Locality. 



12+ 



Museum of Comparative Zoologij. 

 Feb. ] 



Cape Florida. 

 St. Tliomas, W. I. 

 Florida. 

 West Indies. 



Smithsonian Institution. 

 West Indies. 



St. Thomas, W. I. 

 St. Tliomas, W. I. 

 St. Thomas, W. I. 



T. Lyman. 

 A. II. Riise. 

 O. Wurdeman. 

 Univei'sity Museum, 

 Copenhagen. 



University Museum, 



Copenhagen. 

 A. H. Riise. 

 A. H. Riise. 

 A. H. Riise. 



Alcoholic 

 Dried. 



OpMactis Krebsii Lutken. (Figs, lo, ii.) 



Opldaclis Krebsii LiJTKEN. Addit. ad Hist. Oph., p. 126. 



Special Marhs. — Commonly six arms and five arm-spines. A very 

 slight lobe on the outer side of the upper arm-plates. Four moutli- 

 papUlae to each angle of the mouth. 



Description of a Specimen. — Diameter of disk, 3.3"""- ; from outer 

 side of mouth-shield to outer corner of opposite mouth-slit, 1.6"""- ; width 

 of arm without spines, .9"""-; length of arm, 19™""- ; distance from outer 

 side of mouth-shield to inner points of teeth, to that between outer 

 corners of mouth-slits, .8 : .8. Mouth-papillae, ^,.^, ^^ 



four to each angle of the mouth, flat, thin, 

 rounded, longer than broad. Teeth six, upper- 

 most one tapering and a little the longest ; the 

 rest flat, squarish, longer than broad, with a 

 cutting edge thickened at its middle point. 

 Mouth-shields much rounded diamond-shape, 

 with a little tail on the outer side ; length to 

 breadth, .4 : .3. Side mouth-shields stout, barely 

 meeting -within. Under arm-plates about as long 

 as broad, octagonal, the inner lateral sides being 

 longest; length to breadth (tenth plate), .4 : .4. 

 croaching a little below, projecting laterally a good deal. Upper arm- 

 plates oval, thick, slightly swollen, with a very small lobe on the outer 



Side arm-plates en- 



