72 ECHINODERMS OF THE BRITISH LSLE8 



the two upper marginal plates in the middle of the interradii 

 without a larger spine ; no pedicellariae. 



A third species, Pontaster perplexus Perrier, found near the 

 Cape Verde Islands (ca. 1300-2320 m., " Talisman "), is stated to 

 be intermediate between tenuispinus and venustus, and may 

 perhaps not be a separate species. 



1. Pontaster tenuispinus (Diiben and Koren), (Fig. 40.) 



(Syn. Astropeclen tenuispinus Diib. and Kor., Archaster 

 tenuispinus (Diib. and Kor.), Pontaster hebitus Sladen, 

 P. limhatus Sladen, P. Marionis Perrier.) 



Paxillae of dorsal side small, often with a somewhat longer 

 spine in the middle, especially in the outer part of the arms. 



Fig. 40. — Pontaster tenuispinus. Nat. size. (From Danmark' s Fauna.) 



Upper marginal plates with a single prominent spine in the 

 middle, lower marginals with a larger spine near the upper edge 

 and a series of spines decreasing in size downwards. Marginal 

 plates otherwise covered with fine spines, the proximal lower 

 marginals being sometimes more or less naked in the middle. 

 Furrow spines 5-6, in larger specimens up to 10-12, the middle 

 one generally slightly the longest. 2-3 larger spines on the 

 adambulacral plates, outside the furrow spines. Arms varying 

 much in length, R = ca. 3-5-7 r. They taper to a fine point. 

 Papularium small, of an elongate, lens-like form. Colour in life 

 a magnificent red or pink or orange ; the oral side whitish. 

 Grows to a size of ca. 13 cm. R. 



