168 Mr. W. K. Fisher on Asteroidea. 



Verrill * set aside symhoUcus and hipunctus under the name 

 jS'ereidaster, which is synonymous with JRosaster, Perrier, 

 1894. The type of J^ymphaster must be chosen from the 

 tliree remaining species, and for this purpose Xymp>haster 

 protentiis is best adapted. It may therefore serve as the type 

 of Nymphaster. The use of the name Dorigona for this 

 group i^', of course, quite indefensible, since Dorigona is a 

 pure synonym of Ogniaster. Nor can the name Nyniphaster 

 be restricted to symhoUcus and allies, as Dr. Koehler suggested 

 in 1910 tj since the species in question was made the type of 

 Nereidaster in 1899. 



Iconaster versus Dorigona. — In tlie paper on Australian 

 echinoderms already referred to, Dr. H. L. Clark, on page 36, 

 aro;ues that the sea-star known as Iconaster longimanus 

 (Mobius) should be called Dorigona longimana for the 

 foUowino- reasons : — Dorigona, as diagnosed by Gray in 

 1866, included two species — D. reevesii and D. longimana 

 i = Astroqoninni longinianum, Mobius). The first species is 

 held, without dissent, to be synonymous with Guniodiscus 

 capella, Muller & Troschel, 1842, whicli in 1S65 had been 

 made the type of Ogmaster by von Martens. In 1889 

 Sladen made the second species — namely, D. iongimajia — the 

 type of Iconaster. Dr. Clark states that Gray designated no 

 type, and that since D. reevesii is invalidated by having been 

 made, under another name, the type of Ogmaster, " Dorigona 

 longimana (Mobius) must be the type of Dorigona, and I am 

 quite unable to see why Sladen should have deliberately 

 replaced Gray's name with one of his own coining — Iconaster. 

 So far as I can see, Iconaster is a pure synonym of Dorigona, 

 which is a monotypic genus with Astrogonium longinianum as 



i's type." 



Let me quote Gray's characteristically brief diagnosis % : — 



"V. Dorigona, Body depressed. 5-rayed, smooth; the 

 dorsal and oral disk covered with many smooth, flat, polygonal 

 squares ; the marginal ossicules without an}' mobile spine. 



" 1. Dorigona Reevesii (t. 7. f. 3). Inhab. China or 

 Japan ; common in boxes of insects brought from China and 

 Japan. 



" See a. Dorigona longimana = Astrogonium longinianum, 

 Mobius, Ahhandl iv. (1860) 7, t. 1. f. 5, 6." 



* Trans. Connecticut Acad. vol. x. 1899, p. 186. 



t ' An Account of the Shallow-water Asteroidea (Echinoderma of tlie 

 Indian Museum),' Calcutta, 1910, p. 60. 



t ' Synopsis of the Species of Starfish in the British Museum,' by 

 John Edward Gray, 1860, p. 7. 



