Mr. Gray's Reptj/ to Mr, Swainson. 523 



(4) ^THERiA iub'fera, testa irregular! (forma speciminis trans- 

 versa) valva superiore spinis irregularibus tubulosis con- 

 spers^. 



This species, like the other ^theriae, is extremely irregular in 

 its form : it is of a dull green colour and iridescent within ; the 

 outer surface of the upper valve is of a dark blackish green, ex- 

 cept where it is eroded, and it is sprinkled over with large irregular 

 tubular spines. From an examination of this specimen, together 

 with one of j^theria Lamarckii in the Tankerville Collection, 

 I have ascertained the meaning of Lamarck's " callosite oblongue 

 dans la base de la coquille," which is actually only the termina- 

 tion of the ligament, which in this genus, as in Unio, Anodon, 

 and others of Lamarck's Naiades is placed in a sinus ; aflfording 

 another mark of analogy with them, and probably an evidence of 

 affinity as an osculant genus. 



Art. LXIV. Repli/ to Mr. Swainson on Neritina Corona 

 and 31elania setosa. Bt/ John Edward Gray, Esq. 

 M. G. S. 



[Tt the Editors of the Zoological Journal.] 



Gentlemen. 



Mr. Swainson, in his remarks on my account of the Melania 

 setosa, asserts, firstly, that in quoting Lister t. 1055, f. 8, for his 

 shell, I set aside the authority of Limiceus, Gineliii, Martini, and 

 Lamarck ; secondly, that his shell, although not new to science, 

 has never been described or publicly recorded ; thirdly, that the 

 spines of Neritina Corona are not tubular. That these assertions 

 are unfounded, 1 ll.ink the following facts will prove. 



In the twelfth edition of the Systcma Natural of Linnaius, the 

 figure of Lister mentioned above is not at all cited ; neither is it 

 referred to by Martini in his Conchylicn Cabinettc. The con- 

 tinuator of this work, Chemnitz, docs indeed mention it as a 

 " notable variety" of the Papal Crown, which, in liis irregular 



