104 Mr. H. J. Carter on the Nomenclature of the Tethyadse. 



Tethya lyncurium'^ ] and in Deshayes and Milne-Edwards's 

 edition of Lamarck (1836-45) Tethya lyncurium and T. cra- 

 nium are still continued under the head of Tethya\. In 1867 

 Dr. J. E. Gray adopted Nardo's name of Donatia in part for 

 the genus of D. aurantmmX ; and in 1870 Schmidt called 

 Tethya cranium by the name of Tetilla cranium^, adding it 

 to his genus Tetilla of 1868 ||, but still retaining the name of 

 Tethya for Tethya lyncurium. 



Thus Nardo would change Tethya lyncurium to Donatia 

 aurantium, and Schmidt retain the former but change Tethya 

 cranium to Tetilla cranium, while Dr. Gray adopts Nardo's 

 name for T. lyncurium, and continues Tethya for T. cranium. 



Now, in the ' Annals ' of 1869 (/. c), I have described and 

 illustrated Tethya arahica (which is almost identical with T. 

 cranium) in conjunction with Tethya lyncurium, partly for the 

 pm-pose of contrasting the differences between them ; and any 

 one who chooses to refer to this will at once see the wisdom 

 of Nardo in giving a new name (that is, '"''Donatia aurantium^'' 

 called after Donati, the first describer) to Tethya lyncurium ; 

 while any one referring to Dr. Gray's proposed arrangement, 

 may equally see the wisdom of retaining the term " Tethya " 

 for the Tethyadee of which T. cranium is the type specimen, 

 since so great are the differences between Tethya lyncurium 

 and T. cranium, that it was impossible for these two sponges 

 to be long continued under the same generic distinction. 



Nardo, then, changed the name of T. lyncurium to Donatia 

 aurantium in 1833, and Gray adopted this in 1867, still re- 

 taining the name of " Tethya " for the Tethyad?e of which T. 

 cranium is the type specimen ; and there, I think, Schmidt 

 would have done well to have left it, instead of not only re- 

 versing Nardo's change, but of introducing a new term, viz. 

 that of " Tetilla^'' for tlie Tethyadae of which T. cranium is 

 the type, in 1868. 



An apres-moi-le-deluge system of adding new names to ob- 

 jects of natural history unnecessarily is most undesirable. If 

 it be necessary to change the name when two totally different 

 species have been placed under the same generic heading, this 

 change, when once effected, should be considered inviolable ; 

 and this precedence and propriety give in favour of Nardo. 



Hence I shall continue, with Dr. Gray, to use the term 



• Isis, 1833, p. 622 (ib.). 

 t Lamarck, Anim. sans Vert. vol. ii. p. 592. 



X " Notes on the Arrangement of Sponges," Proc. Zool. Soc. May 1867, 

 p. 541. 



§ Atlant. Spong. Faun. p. 66. 

 II Spong. Kiiste Algier, p. 40. 



