194 



Troschel, System der Ästenden, 1842, page 22, footnote, as the type 

 of their genus Echinaster. 



The distinction between the restricted Echinaster and Othilia may 

 seem a trifle subtile. In practice, however, it has not been difficult to 

 use the two groups — at least so far as species which I have personally 

 examined are concerned. It may be noted that the same difference se- 

 parates Henricia and Cribraster, the latter corresponding to Echinaster. 

 The following notes will present my reasons for retaining the name 

 Othilia for the American species. 



The original description ^ of Echinaster is not accessible but it was 

 reprinted 3 in September of the same year in the Archiv für Natur- 

 geschichte, with the following enumeration of species: "4 Arten: Ä. 

 sepitosa Lam. [= A. seposita], A. echinophora Lam. [Pentadactylosaster 

 spinosus Linck), E. spongiosus Nob. (Linck, t. 36, n. 62) und eine neue 

 Art". As a footnote is the following: '■'Echinaster ist der älteste von 

 Luidius und Petiver für ein hierher gehöriges Tier gebrauchte Name." 

 There was no designation of type. Two years later in the System der 

 Ästenden, p. 22, the species of Echinaster are cited in different order, 

 namely: spinosus, b?'asiliensis , crassus, gracilis ^ sepositus^ fallax^ eri- 

 danella^ serpe7itarius, oculatus, eschrichtii, solaris. In a footnote refer- 

 ring to Echinaster., the note quoted above is somewhat amplified as fol- 

 lows: "Ein von Luidius, Petiver und Linck zur Bezeichnung eines 

 hierhergehörigen Tieres, J.sfenas echiìiophora Jjàm.., angewandter Name." 

 This seems to me to be not a designation of type but an explanation of 

 the derivation of the new generic name, employed previously by Pe- 

 tiver in the following polynomial: "Echinaster seu stella coriacea penta- 

 dactyla echinata". Asterias seposita was given first place in the ori- 

 ginal description of Echinaster and it is reasonable to consider the 

 European species as the type. 



Stellonia Nardo (De Asteriis, Oken's Isis, 1834, p. 716) included 

 Asterias ruhens, seposita., glacialis, and spinosa but without generic dia- 

 gnosis. Lest the ghost of this name arise at some future time, it may 

 be "laid" by definitely designating Asterias ruhens as the type, making 

 Stellonia a synonym of Asterias, s. s. 



According to the view expressed in my key to the genera of Echin- 

 asteridae, the generic groups would stand as follows. 



Mchinaster Müller and Troschel, 1840. 

 Type Echinaster sepositus. Species examined: E. sepositus, E. 

 callosus von Marenzeller, E. stereosomus Fisher. 



2 Monatsber. d. k. preuß. Akad. d. Wiss. Berlin, April 1840. p. 102. 



3 Archiv f. Naturgesch. 6. Jahrg. Bd. 1. p. 321. 



