ASTEROIDEA 



65 



1. Persephonaster 2)(itagiatu.s (Slsiden). (Fig. 37.) 



(Syn. Psilaster patagiatus Sladen ; Psilasteropsis imtagiatus 

 (Sladen).) 



Upper marginal plates covered with minute, scale-like spines ; 

 lower marginals with the same general covering, but with an 

 oblique series of 3-5, or even as many as 10, long, slender, ap- 

 pressed spines along the outer edge. Adambulacral plates with 

 a comb of ca. 10 slender spines (sometimes more, up to 17) ; 



Fig. 3" 



-Persephonaster x)atagiatus, oral and aboral side, 

 in size. 



Slightly reduced 



outside these are found some smaller spines more or less dis- 

 tinctly arranged in two longitudinal series. The spines on the 

 oral interradial plates, which are of the same general character 

 as those on the adambulacral plates, may be grouped so as to 

 form simple pedicellariae. Also on the upper marginal plates 

 there may be a kind of incipient pedicellariae. Paxillse of the 

 dorsal side of arms fairly large, arranged in distinct transverse 

 rows along the sides. Towards the point of the arms the upper 

 marginal plates join in the middle line. Terminal plate rather 

 long, apparently ending in a large, conical medial spine and a 



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