74 



ASTEKOIDEA. 



longer than those of the outer but are not so stout. The inter- 

 mediate plates uniformly but coarsely granulated, the granulation 

 much coarser than that on the marginal plates, from which it 

 becomes more or less lost. The plates of the dorsal surface regu- 

 larly hexagonal or sometimes irregular, covered by broad flat 

 granules. Madreporite inconspicuous. 

 Colour, dried, white. 



Distribution. Both sides of North Atlantic ; to Arctic Ocean and 

 White Sea on the east. 20-750 fms. 



a, b. Faeroe Channel, 440 fins. 



'Porcupine' Exp. (St. 51). 



2. Pentagonaster greeni. 

 Astrogonium greeni, Bell, Ann. Sf Mag. iv. (1889) p. 433, pi. xix. 



fig. 4. 



E = 27, >-=12-5. 



The curve between the arms is well rounded ; there are seven or 



Pentagonaster greeni. 



eight supermarginal and seven to nine inferomarginal plates; those 

 of the upper and lower series do not correspond regularly ; the 



