Indian Deep-Sea Asteroidea. 93 



sionally either a central large " florigerous " spine or a large 

 obovate pedicellaria. 



Anus central. Madreporiform plate small, radially striated, 

 placed a little nearer to the centre than to the margin. 



Colour in life a network of cinnabar-red on a yellow 

 ground abactinally. 



Andaman Sea, 230 to 290 fathoms. 



I have named this magnificent species after its discoverer. 



DORIGONA, Gray. 

 26. Dorigona pentaphylla, sp. n. 



A magnificent species, very near to Dongona longimana^ 

 Mobius. 



Rays 5. Pt = 3-25 v. R=115 millim. in the 

 type specimen. 



Disk large, flat, pentagonal ; rays long, broad at base, 

 tapering. All the plates — actinal, marginal, and abactinal — 

 except the adambulacral perfectly smooth and edged with 

 foliaceous granules lying flush with the general surface. 



Abactinal surface of the rays entirely occupied by the 

 supero-marginal plates, which from the seventh onward meet 

 across the ray ; abactinal surface of the disk covered with 

 hexagonal plates, of which those in a broadly ovil petal- 

 shaped area in each radius are distant regular hexagons — in 

 the mid-radial line of predominant size — with long tentacle- 

 like papulas standing near the angles, while those in a trian- 

 gular area in each interradius are crowded irregular hexagons 

 without any papulae intervening. 



The marginal plates number about 30 in each series, 

 measured from mid-intcrbrachium to tip of ray ; they are 

 broad massive squares and form a broad margin on both 

 surfaces ; the supero-marginals from and including the 

 seventh meet across the ray in a zigzag suture; the infero- 

 marginals are smaller than the supero-marginals and alternate 

 with them, except in the interbrachia, where the two series 

 nearly correspond. 



The adambulacral plates are small ; each has a semicircular 

 furrow-series of small foliaceous spinelets — ten or eleven in 

 number in the basal half, eight to six in number in the apical 

 half of the ray — of which those at the ends of the series are 

 thickened, while actinally there are three irregular longitudinal 

 rows of depressed granules ; most of the plates near the 

 actinostomal end have a central bivalve or trivalve pedi- 



