596 ]Mi'. W. K. Fisher — Soles on Asttroidea. 



plates are juiueJ to the superoinargiiials by transverse bands 

 of plates whieli are a little more regular than the others, and 

 between consecutive fnibeculce are broad (but short) papular 

 areas, which form a zone just above the su[)eromarginal 

 plates. These papular areas, or skeletal meshes, are larger 

 than the otluM" abactinal and the intermarginal meshes. The 

 marginal pbites are fairly robust and of the form usually 

 found in the Asteriinse — namely, four-lobed. The descending 

 lobe of the superomarginal is the longest, and strongly 

 overlaps the ascending lobe of the inferomarginal. The 

 superomarginals are regularly monacanthid, while jnost of 

 tlie infe:omarginals are diplacaiithid. There is a very incon- 

 sj)icuous series of small spineless actinal plates. 



The skeleton is as well developed as in some specimens of 

 Sporasterias antarctica which I have examined. 



The gonads are not present in all rays, and are attached to 

 the body-wall on a level with the siiperomarginals ; but the 

 duct turns downward, and I believe that I have demonstrated 

 its external opening on the ventral surface, on a papilla, 

 close to the interradial line. 



I propose to separate this species from Lysasterias under 

 the generic title of JiceJderaster, in honour of Dr. Rene 

 Kadiler, of Lyons, well known for his numerous admirable 

 papers on Antarctic echinoderms. 



Ka'Jileraster difiers from Lysasterias in having an open but 

 perfectly normal, irregularly reticulate, abactinal skeleton 

 and well-developed marginal skeleton. It differs from the 

 species of Sporasterias in possessing a thick, highly pustu- 

 lated, " ca.uliflower " skin. 



Purastichaster, Koehler (' Asteroidea, Australian Antarctic 

 Expedition,' p. 89). — Type, P. mawsoni, Koehler, first species. 

 In addition to the six-rayed type. Dr. Koehler describes two 

 other species — direclus, having 5 rays, and spkoerulatics, with 

 G or 8 i-ays. These are stout-rayed monacanthid sea-stai's, 

 iiaving a rather irregular dorso-lateral skeleton, small caiinals, 

 and relatively n)uch smaller superomarginals than in Slick- 

 aster, to which Koehler compares the new group. The 

 gonads open ventrally and the young are carried in a cluster 

 over the mouth. The stubby inferomarginal spines are 

 arranged in short, oblique, transverse series. 



All these features are characteristic of Sporasterias spira- 

 hids (Bell) and adult S. riiyispina (Stimpson). In fact, 

 Paruslichaster inatcscni suggests a six-iayed Sporasterias 

 ■"■piraOilts. The [ a'd(i})horic liabit and niunacanthid adambu- 



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