36 ‘‘ ENDEAVOUR” SCIENTIFIC RESULTS. 
Genus NyMPHASTER, Sladen. 
As regards the generic name, it is to be regretted that 
Koehler still persists in using Dorigona in place of Nymphaster. 
Sladen, in 1889, Verrill, in 1899, and Fisher more recently, 
have pointed out that Dorigona is not one of Perrier’s genera, 
but dates back to Gray. Its type is either D. reevesii, Gray or 
D. longimana (Mobius) ; no other species can be the type since 
these are the only species mentioned by Gray, who, however, 
designated no type. It has been shown, and, so far as I know, 
never questioned, that D. reevesiz, Gray is synonymous with 
Goniodiscus capella, Muller and Troschel, 1842. Now von 
Martens constituted a subgenus, Ogmaster, for G. capella in 
1865, a year before Gray proposed Dorigona. All later writers. 
have agreed that G. capella is entitled to generic rank and, 
including Koehler himself, use Ogmaster capella as the correct 
combination. Hence Dorigona longimana (M6bius) must be 
the type of Dorigona, and Lam quite unable to see why Sladen 
should have deliberately replaced Gray’s name with one of his. 
own coining, /conaster. So far as I can see [conaster is a pure 
synonym of Dorigona, which is a monotypic genus with 
Astrogonium longimanum, Mobius, as its type. 
It is evident then that Nymphaster and Dorigona are not in 
any way equivalent terms. Koehler proposes to restrict Nym- 
phaster to the forms in which the superomarginal plates are 
separated by a single median row of abactinal plates and use 
Dorigona for the forms in which the superomarginal plates are 
in contact dorsally. It is, of course, obvious that Dorigona 
cannot be used in any such way. Moreover Verrill, in 1899, 
proposed Nereidaster for the species with separated supero- 
marginals, and restricted Nymphaster to the species which 
Koehler would call Dorigona. This he was perfectly justified 
in doing, for Sladen designated no type for the genus in which 
he included five species. Clearly Dorigona, Koehler, is a 
perfect synonym of Sladen’s Nymphaster as restricted by 
Verrill, and has no close relationship to Dorigona, Gray. It 
is to be hoped, therefore, that our able and honoured French 
colleague will no longer reject Nymphaster and will confine 
Dorigona to Mobius’ remarkable species. 
NYMPHASTER PENTAGONUS,! sp. nov. 
(Plate VIII., fig. 1-2.) 
R=60 mm. or thereabouts; r=18mm.; R=3.3r. Br= 
10 mm.: R=6 br. Br at middle of ray, 6 mm.; at tin, 
1. Pentagonus=with five angles, or, as usually understood, five-sided + 
in reference to the nearly straight-sided area of abactinal plates. 
