JAPANESE ASTEROIDEA. 95 



in others, tlie appearance being lieiglitenecl by racm-ved rays, when the 

 actinolateral angle is rounder and less abrupt. The exposed surface of the 

 specialised ridge of superomarginal x^lates is thin or narrow, but varies more 

 or less, being sHghtly broader in four Atlantic sijecimens ; but in another 

 Atlantic example from off Newfoundland they are as narrow as in Alaskan 

 specimens. The height of ,superomarginals is variable, specimens from 1,033 

 fathoms having much lower ones. This is readily appreciated by noting the 

 distance between the two series of marginal spines in the interbrachial arc. 



" Adinal surface. — The adambulacral armatm-e is essentially aHke in both 

 Atlantic and Pacific s^^ecimens, some examples showing a preponderance of 

 tln-ee or four spines, others of four and five. Besides the spine (not of 

 fmTow series) wliich usually stands on the outer aboral corner, there is usually 

 one to several very much smaller and more dehcate spinelets along adorai 

 and outer edge of plate. These can not be distinguished readily unless 

 specimen is dry. 



"Actinal interradial area, like marginal and adambulacral plates, are 

 overlaid by membrane tln-ough Vv^hich the plates are scarcely visible until 

 dried. Plates are an-anged in series running from marginals to adambula- 

 crals. Deex? channels also follow the same com'se. These are overhung by 

 a series of spinelets embedded in membrane, being a continuation of the 

 marginal fascioles. The interradial channel sphts and rims on either side of 

 mouth plates. The fii-st on ray always runs between second and third 

 adambulacral, the second between the tliird and fom-th, and so on. The 

 photographic figm'e will show the arrangement of plates. 



" Anatomical notes. — No intestine, no intestinal cœcum, no anus. The 

 conical eminence in centre of disk contains a prolongation of the cœlom and 

 is divided by a vei-tical septum. Stomach large, single, fii'mly moored to 

 abactinal waU. Hepatic coeca large, extending nearly to end of ray, and with 

 spacious cavity. Gonads interradial, one on either side of the membranous 

 interradial septum. Ampullae single ; tube feet large, conical, pointed ; no 

 dex^osits in walls ; one PoHan vesicle to each inten-adius. 



" Superambulacral plates present ; absent from fii'st and sometimes second 

 ambulacral ossicle and also from last six or eight at end of ray. These plates 



