Indian Deep-aca As/eroi'tlra. 97 



series so as to luiiii a circular ]):tlis;i(lc ri>nml cacli isolated 

 pair of tubc-lect. 



Actinal interradial areas large, the irregularly quadrangular 

 and closely granular internicdiate plates being arranged in 

 concentric chevrons and numbering about fifty in each area. 



Madreporiforni plate very snuill, with coarse radiating 

 striations ; placed close to the centre, encircled by three much 

 larger plates, the adcentral of which — the largest of all — is a 

 basal interradial. 



Andaman Sea, 490 fathoms. 



Pakagonasteh, Sladen. 



31. Paragonaster tenuiradiis^ sp. n. 



Rays 5, R = 4'o r. 11 = 40 millim. in the 

 type specimen. 



Disk pn-:al], pentagonal ] rays long, extremely slender, oval 

 in section, rigid. 



The abactinal area of the small disk bears large crowded 

 paxilliform ])lates arranged in regular chevrons and closely 

 covered with angular flat-topped granules, the mid-radial 

 plates being the largest and the mid-interradial plates the 

 smallest of all ; the narrow abactinal surface of the rays bears 

 a single series of narrow granular j)lates intervening between 

 the supero-marginal plates of opposite sides. 



The marginal ])lates, which are large and closely covered 

 with angular granules, number over twenty-five in eacii series ; 

 the supero-margintils, which are a good deal larger than the 

 infero-marginals, aie almost entirely lateral on the disk, but 

 largely abactinal on the rays, where those of ojiposite sides 

 are separated only by a narrow series of abactinal plates ; the 

 infero-marginals alternate (more markedly in the distal iialf 

 of the ray, less markedly in the interbrachia) with the supero- 

 n)arginals, and those in the interbrachia bear a median vertical 

 series of two to four small spines or spinelets. 



The adambulacral plates bear a semicircular marginal 

 series of nine or ten radiating spinelets encircling a few 

 distant actinally-])laced spinelets, of which one, standing- 

 close to the middle of the marginal series, is more conspicuous 

 than the rest. Mouth-plates prominent actinally, with a close 

 furrow-series of ten or eleven spinelets and a single suture- 

 series of nine or ten spinelets. 



Actinal interradial areas small, barely reaching to the third 

 infero-marginal jdate ; in each area there are about thirty 

 minute scale-like plates bearing distant papilliform granules. 



