Indian Deejj-sea Asteroidea. 107 



41. Zoroaster carinatus, sp. n. 



Rajs 5. E. = about 10 r. R=- about 90 millim. in 

 the type specimen. 



Disk small, liemisplierical, higher than the rays j rays 

 semicylindrical, strong-ly carinatecl, tapering in the distal half, 

 but not much diminishing in the basal half. 



Abactinal surface of disk with close-set, large, tumid, 

 stellate, primary radials and basals surrounding a very promi- 

 nent dorso-central plate and a ring of small depressed under- 

 basals ; all the plates are densely covered with thorn-like 

 spinelets, which are enlarged in the middle of the plate ; 

 isolated papulce surround the plates, and a few small scattered 

 pedicellaria3 occur. 



Rays with a median longitudinal row of very large and 

 tumid stellate plates, closely covered with spinelets, of which 

 those in a tuft in the middle of each plate are enlarged. On 

 each side of this median row is a depressed discontinuous 

 series of very small irregular platelets, below which are live 

 parallel rows of close-set tumid octagonal plates ; all these are 

 closely covered with thorn-like spinelets, and those of the 

 four lower rows have also a long slender median spine. The 

 minute apertures between the angles of neighbouring plates 

 (except between those of the two lowermost rows) give exit 

 to a single papula, and close to every papula is a small 

 pedicel laria, 



Adambulacral plates small, cylindrical, each with a trans- 

 verse series of two (rarely three) long slender spinelets ; every 

 alternate plate has a prominent intra-ambulacral ridge bearing 

 a row of two or (usually) three similar but larger spinelets, 

 one of which, within the furrow, has occasionally a small 

 pedicellaria, or sometimes two. Mouth- plates with long 

 spinelets like those of the ordinary adambulacrals. 



Tube-feet quadriserial. 



Madreporiform plate very small, hardly one third the size 

 of the basal plate outside of which it lies. 



Colour in life brick-red. 



Andaman Sea, loO to 250 fathoms. 



This species, which is one of the commonest starfishes met 

 with in the Andaman Sea between 200 and 300 fathoms, is 

 characterized, (i.) by the dense thorny armature of the very 

 tumid apical plates, each of which has a central tuft of 

 enlarged spinelets; (ii.) by the strong carination of the rays, 

 which is due partly to the tufts of enlarged spinelets of the" 

 tumid mid-radial low of plates and partly to the sinking of 



8* 



