MUSEUM OF COMrARATIVE ZOuLOGY. 157 



OPHIOSCOLEX Mull, and Trosch. 

 Ophioseolex dentatus sp. nov. 



Plate \1I. Figs. 184 - 186. 



Special Marks. — Three or four short, blunt, flattened arm-spines. Numer- 

 ous mouth-papillae, whereof the outer are flat spiniform. One tentacle-scale. 



Description of an Individual (Station 142). — Diameter of disk 15 mm. 

 Length of arm about 55 mm. Width of arm, without spines, close to disk 

 2.7 mm. There are seven mouth-papillae on each side of an angle and one 

 small and pointed at apex of jaw ; the three outer are flat spiniform, and much 

 the largest and longest. On removing the skin the mouth-shield is seen to 

 be wide triangular, having an obtuse angle within and outer corners rounded. 

 Side mouth-shields long, narrow, and meeting within. Arms covered by a 

 thick skin completely hiding the plates, which are obscurely indicated below 

 by transverse furrows. On removing the skin, the under arm-plates appear 

 longer than wide, with a curv^e without and a re-entering curve within ; the 

 side arm-plates small and meeting neither above nor below, while the upper 

 plates are only indicated by thin films of slightly calcified skin. Disk round 

 and rather flat, covered with a soft naked skin variously WTinkled above and 

 below.* Genital openings wide and long, extending from the mouth-shield to 

 the edge of the disk. Three or four short, blunt, flattened arm-spines, equally 

 spaced, about as-long as an arm-joint ; the upper and undermost usually a little 

 the longest. One small rounded tentacle-scale on the inner side of the pore. 

 Color in alcohol, light gray. 



Station 142, off Agulhas Bank, 150 fathoms, 12 + specimens. 



Ophioseolex tropicus sp. nov. 



Plate VII. Figs. 190 - 192. 



Special Marks. — Seventeen to nineteen small, short, pointed close-set mouth- 

 papilla), occupying the entire margin of ^ach mouth-angle. Whole animal cov- 

 ered by a thick skin, through which appear the lower and side arm-plates, 

 the mouth-shields, and (indistinctly) the scaling of the lower interbrachial space. 



Description of an Individual (Station 24). — Diameter of disk 8 mm. Width 

 of arm close to disk, without spines, 1.3 mm. Eight or nine short, close-set, 

 rounded mouth-papillae, occupying the whole length of each side, and one larger 

 and more pointed at apex of jaw. ]\Iouth-shields much broader than long, in shape 

 transverse oval ; length to breadth .6 : 1.2. Side mouth-shields long, curved 

 and narrow, broader without, tapering inward, where they do not quite meet. 

 First under arm-plate very small, nearly square, the others larger, long hexago- 

 nal, with outer side curved, lateral sides re-enteringly curved, and three inner 

 sides short. Side arm-plates broad and thin, meeting near base of arm neither 

 above nor below. The place of the upper arm-plates is occupied by thick skin, 



* It is not often so regularly wrinkled as in Fig. 185. 



