108 The Genera of the PlumulariidcE,. 



Sertularella purpurea, K. — This species (from the 

 Chatham Islands) seems to me to differ little, if at all, from^ 

 the ordinary New Zealand form of S. Johnstoni. Some of 

 my specimens of the latter form agree with Kirch enpauer's 

 in being of a beautiful purple-red throughout, but other 

 parts of the same material are of the ordinary yellowish- 

 brown colour, showing that the red tint is not a specific 

 feature. I have met with the same variation of colouring 

 in Flumularia BusJcii, and Johnston mentions its occasional 

 occurrence in some of the British Sertularians. 



On Thuiaria Zelandica, Gray, By J. J. Quelch, B.Sc» 

 (Lond.), Assistant Zoological Department, British 

 Museum (Annals and Magazine of Natural History _, 

 April, 1883). 



The author of the above paper has ascertained from an 

 examination of some of Gray's specimens of Thuiaria 

 zelandica that the T. dolichocarpa of AlJman is the same 

 species, and proposes to abolish the latter name in favour 

 of the older one, in which he has been followed by Kirchen- 

 pauer. To admit the claim of priority in such a case as 

 this, however, would be to ignore the first principle of 

 scientific nomenclature, which requires that for a specific 

 name to obtain acceptance it must be accompanied by a 

 description at least sufficient for the identification of the 

 species with a reasonable degree of certainty. Gray's 

 definition is entirely worthless, hence the species should 

 continue to bear the name bestowed upon it by Professor 

 Allman, who first gave a proper description of it, accom- 

 panied by careful figures. On the same principle Mr. 

 Hincks retains the name of Ga7)ipanulina acuminata (Alder) 

 for a species which had been found to be identical with the 

 earlier G. tenuis (Van Beneden), on the ground that Van 

 Beneden's description was not sufficient to enable the species 

 to be recognised. 



It appears to me that tlie laws of nomenclature can only 

 be properly appealed to in order to decide which of two or 

 more proposed names has the better claim to acceptance, 

 and not to interfere with names which have already become 

 generally adopted. On the opposite plan we should be 

 obliged, for example, to abolish the universally received 

 ' Halicornaria of Allman in favour of Hincks' name, Gymnan- 

 gium, applied previously to the same group. 



