262 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



It is greatly to be regretted that Koehler has lent the weight of 

 his authorit}' to such an obvious misuse of a name as that of 

 Dorigona. There is no possible excuse for the use of this name for 

 Xym,phaster. 



In assuming to call this genus Dorigona (Gray, 1866, p. T) it is 

 also necessary to assume that Gray's genus included originally one 

 or more true Nyiri'p'haster^ which, as is well known, it did not. The 

 type of the genus is Dorigona reevesii, the same species as Ogmas- 

 ter capella von Martens (1865). Dorigona is therefore synony- 

 mous with Ogmaster and its status in nomenclature is fixed for 

 all time. It is true that Gray mentioned another species, Astro- 

 gonium longimanum Mobius, but this is not congeneric with Dori- 

 gona reevesii^ and is given a distinctly" secondary place by Gray. 

 Sladen made it the type of his new genus Iconaster^ in 1889. It will 

 be noted that no true Nymnyliaster is mentioned, and, in fact, this 

 group was not discovered until many years afterward, during the 

 expeditions of the Challenger and the Blake. 



The following is a short history of the name in Perrier's writings. 

 In 1875 in the " Eevision," p. 228. Dorigona is used as a subgenus 

 exacth^ in the sense that Gray uses the name in his " Synopsis " of 

 1866, with the exception that Ogmaster capella is called Pentagon- 

 a^ter mulleri instead of Dorigona reevesii. Astj^ogoniuin longimanum 

 is listed under the name Pentagotiaster longimanvs. In 1884 

 Pentagonaster ternalis, P. subspinosus, and P. arenatus are described 

 from the Blake collections, but no mention is made of Dorigona. 

 But in the following year ^ the last, and a new species, prehensilis, 

 are placed in the " Genus Dorigona Gray " without comment. 

 In 1894, p. 365, we find Dorigona again used in the sense of 

 Nymphastcr. It is interesting to note that Perrier in the syn- 

 onymy omits the original citation, his first reference being to the 

 "Revision" of 1875. He then gives a generic description which 

 obviously applies to Nymplmster and has nothing to do with the 

 genus Dorigona of Gray, let alone the fact that none of Gray's species 

 are included. Perrier himself does not believe that Ogmaster 

 capella is congeneric with Dorigona ternalis, yet by what reason- 

 ing ternalis is placed in a genus of which Ogmaster capella is the 

 type, it is beyond me to discover. His only apology is an observa- 

 tion on page 367 : 



The genus Dorigona, in the sense in which we have just limited it, corre- 

 sponds to the genus Nymphaster of M, P. Sladen, who gave absolutely without 

 necessity a new name to a generic division long since indicated and of which 

 the limits demanded revision in relation to recently discovered genera. 



»Note prelim, sur les fichlnod. dragu6s par le TravaiUeur et le TaUsmatij Ann. scl. 

 nat, 1885. p. 39. 



