SEA LILIES, STARFISHES, ETC. CLAKK. 61 



Genus Echestaster, Muller and Troschel. 



ECHIXASTER ACANTHODES,^ Sp. nOV. 



(Plate xix., fig. 1-2; Fig. 7.) 



R=70 mm. ; r=12 mm. ; R = 6 r. Br=14 mm. ; R=5 

 br. Br at middle of ray=9 mm. ; at tip, 3.5 mm. Disk 

 moderate, slightly arched ; arms terete, tapering very uni- 

 formly to the narrow but blunt tip. Abactinal skeleton 

 coarse and rather heavy ; each plate bears a large sharp spine, 

 .5-1 mm. high. Papulge confined to abactinal surface ; the 

 areas in six irregular longitudinal series, each area ^\ith few 

 (2-6) papulae. Adambulacral armature consisting of 3 spines 

 in a vertical series, the smallest high up in ambulacral furrow, 

 the second, Httle larger, just below, and the third, much 

 larger, on the furrow-margin ; except on the 12-16 plates 

 nearest the mouth, there occurs on the actinal surface of 

 every other plate, a conspicuous subambulacral spine, equal 

 to, or larger than, that on the furrow-margin ; back of this 



Fig. 7.x3. 



spine, on the actinolateral or more Hkely the inferomarginal 

 plate, is another still larger spine, about 2 mm. high. Oral 

 plates with no surface spines and marginal spines united by 

 membrane, which reaches more or less nearly to their tips, 

 and extends outwards along the rays uniting more or less 

 evidently the furrow-margin spines of the first few adam- 

 bulacral plates. Beyond the disk, each spine is more or less 

 clothed in membrane. Madreporite very small, about half- 

 way between disk-centre and margin. Colour (dry), light 

 brown. Three specimens. 



The general appearance of this species is more Hke that of 

 the West Indian Echinasters than hke that of its East Indian 

 congeners. The conspicuous spines and the total lack of 



1- a/cni'^wCH9=full of thorns ; in reference to the spiny surface. 



