OPHIUROIDEA 227 



seas, the species P. vestita Forbes having been found in the Medi- 

 terranean (^gean Sea, 160 m.). The only specimen known was 

 found in the year 1843. Another genus, Ophiarachnella Ljung- 

 man, is known from off the Cape Verde Islands ; the species 

 0. semicincta (Studer) (Sjti. Pectinura semicincta Studer) having 

 been found there in 68-105 m. (" Gazelle ", " TaUsman "). 

 Whether any of these will be found in the British seas is 

 hard to sa}^, but it would not seem very probable. Both are 

 distinguished from Bathy])ectinura by having 2 tentacle scales, at 

 least, in proximal part of arm. Ophiarachnella has naked radial 

 shields, while in Pectinura these are covered by the general 

 granulation. 



Ophioconis Llitken. 



Only one species, 0. Forhesi (HeUer) (Sjm. Pectinura Forbesi 

 HeUer), known from European seas. It has been found in the 

 Bay of Biscay (47° 48' N., 7° 46' W., 196 m., " Huxley "), at the 

 Azores, at the Moroccan coast, and in the Mediterranean. Bathy- 

 metrical distribution ca. 20-200 m. Another species, 0. vivipara 

 Mrtsn., has been found off Cape Blanc, on the Senegal coast, at a 

 depth of 20-30 m. It is not probable that this latter species 

 will occur in the British seas. The two species are thus 

 distinguished : 



Arm spines 7, as long as an arm-joint . . 0. Forbesi (Heller) 



Arm spines 6-5, scarcely half as long as an arm-joint 



O. vivipara Mrtsn. 



The genus Ophioconis is by H. L. Clark referred to the family 

 Ophiacanthidae ; though this seems unacceptable, it must be 

 agreed that its position within the family Ophiodermatidse is not 

 beyond doubt. 



[Family Ophioleucid.^] 



Dorsal side of disk more or less closely covered with granules, 

 which, however, leave at least the large, rounded radial shields 

 naked. ^ Ventral side of disk without granules or, when granules 

 are found, the scales remain distinct. Jaws not set with granules. 

 Mouth papillae numerous, forming a continuous series. A single 

 series of teeth, no tooth papillae. Arm spines appressed, few and 

 small. Second tentacle pore opening into the mouth slit, visible 

 from the outside or not. Very slender and fragile deep-sea forms. 



^ This character applies to the N.E. Atlantic forms, not to the whole 

 of the family. 



