464 Linncean Society. 



self to those belonging to the genus Ophiura, and to an allied genus, 

 hitherto un characterized, to which he gives the name of Pectinura. 

 This genus is founded on a small starfish brought up by the dredge 

 from the depth of 100 fathoms on the coast of Lycia, and is charac- 

 terized as follows : — 



Pectinura. 



Corpus orbiculare, squamosum, granulosum, ad peripheriam radiatum ; 



radii's simplicibus, squamosis, in corporis discum subprolongatis ; squamis 



radiorum lateralibus adpressis, in marginibus superioribus spiniferis ; 



ossiculis ovarialibus binis in corporis lobos non productis. 

 P. vestita, disco orbiculari, radiis convexiusculis ; squamis superioribus 



rotundatis : lateralibus 8 spiniferis. — Lat. disci £ unc. 



Professor Forbes states that he should scarcely have ventured to 

 establish a genus on the single specimen of this species which he 

 possesses, and which is somewhat imperfect in the rays, had he not 

 had an opportunity of examining a large foreign species, which shows 

 it to be a well-marked genus, having a rather closer affinity with 

 Ophiura than with Ophiocoma. It differs from the former in having 

 the disc clothed with granules, in the absence of the pectinated 

 scales embracing the origins of the rays, and in the ovarian plates 

 (not soldered into one as in Ophiura) not encroaching on the body ; 

 and from Ophiocoma by the lateral ray-plates overlapping each other 

 and the posterior ray-plates as in Ophiura, and instead of having the 

 spines on a transverse ridge or keel having them articulated to their 

 superior margins, so that when the animal is dead they lie close to 

 the rays and do not bristle out as in Ophiocoma. 



Of Ophiura Professor Forbes found three species, 0. texturata, O. 

 albida, and a new species to which he gives the name of 0. abyssicola, 

 on account of its being found in deeper w T ater than any recorded 

 starfish, at the depth namely of from 150 to 200 fathoms. A com- 

 parison of the characters of this new species with those of its de- 

 scribed allies, has enabled him to revise the characters of the genus 

 Ophiura as follows : — 



Ophiura, Lam., Agass. 



Corpus orbiculare, squamosum, laeve, ad peripheriam radiatum ; radiis 

 simplicibus, squamosis, in corporis discum prolongates, ad origines 

 squamis pectinatis adpressis ; squamis radiorum lateralibus adpressis, 

 in marginibus superioribus spiniferis ; ossiculis marginis ovarialibus 

 simplicibus, in corporis lobos productis. 



The following are the specific characters of the JEgetrn species : — 

 0. texturata, Lam. Squamis pectinatis ad radiorum origines plus quam 

 20-dentatis, ossiculis ovarialibus lyratis, radiis carinatis ; squamis supe- 

 rioribus transverse oblongis : lateralibus 7 spiniferis. 

 0. albida, Forbes. Squamis pectinatis ad radiorum origines 16-dentatis, 

 ossiculis ovarialibus scutatis, radiis convexis ; squamis superioribus tri- 

 angulares : lateralibus 4 vel 5 spiniferis. 

 O. abyssicola, squamis pectinatis ad radiorum origines binis 5 — 9-den- 

 tatis, ossiculis ovarialibus pentagon is, radiis carinatis ; squamis supe- 

 rioribus quadratis : lateralibus 3 vel 4 spiniferis. — Lat. disci ^ unc. 



