1881.] Mollusoa of ike Indo-Malayan Fauna, 131 



hagen, who contributed several excellent papers towards our knowledge or! 

 the Mollusca of the Nicobars. 



Type, Indian Museum ; centre of Great Nicobar, coll. P. A. de 

 Roepstorff, Esq. 



Genus Nanina., Gray. 



P. Zool. S. 1834, types H. nemorensis, Mull. [Xesta], H. javanensis, Fer. [Xesta], 

 H. exilis, Miill. [Hemiplecta], H. citrina, Lin. [Xesta], H. monozonalis, Lin. [Xesta], 

 H. clairvillia, Fer. [Hemiplecta], H. vitrinoides, Desh. [Macrochlamys], H. Juliana, 

 Gray [Xesta] and N. striata, Gray [Hemiplecta] ; type restricted, Gray, P. Zool. S. 

 1847, p. 169, Helix citrina, Lin.; = Xesta, Albers, 1850, type H. citrina, Lin. ; = 

 " Phereporae," Desmoulins, Bull. Soc. Lin. Bord. Ill, 1829 [name inadmissible] ; 

 pars ? = Stenopus, Guilding, Zool. Journ. Ill, 1828, type S. lividus, Guild. = Guppya, 

 Morch, J. de C. 1867, [as Stenopus had been previously used for a genus of Crustacea.]. 



The type of Gray's Nanina is therefore H. citrina and not H. vitri- 

 noides [Macrochlamys indica, Bs.], as supposed by some authors. 



Benson himself distinctly admits the validity of Gray's Nanina, over 

 his MS. name of Tanyclilamys or Macrochlamys {see Proc. Zool. Soc. 183i, 

 p. 89, J. A. S. B., 1836, and later on in the Annals and Mag.) ; had my 

 Indian conchological friends referred to these papers, or to the J. A. S. B., 

 1832, p. 13, for the original and casual mention, in a footnote, of Benson's 

 MS. name Macrochlamys, I am sure they would never have attempted to 

 introduce so retrogade and useless a change, utterly unwarrantable in every 

 way. Here is Benson's mention of the name in full, — " Those (Pterocyclus 

 sp.) which I found, were, with several specimens of a Cyclostoma, a reversed 

 Carocolla and Macrochlamys ;" — then follows a foot-note, — " A new genus 

 of the Helicidae separated by me from Helix, in consequence of the wide 

 departure of the animal from the type of that genus." With this and a 

 mere repetition of the name on page 76, ends the so-called description of 

 Macrochlamys in 1832, although never claimed as such by Benson himself. 



Many authors (Benson included) speak of his genus Tanyclilamys as 

 having been described in the Proc. Zool. Soc. 1831, but as far as I can trace 

 this is not strictly the case. Benson appears to have sent a paper to the 

 society containing an excellent description of the section, with the name 

 Tanyclilamys attached ; the editor, however, changed it to Nanina, stating 

 that it had been found to be the same as Gray's genus described a few pages 

 previously ; in the description the editor casually mentions that the form 

 described was the Tanyclilamys of Benson, MS. It is very doubtful if 

 Stenopus is a section of Nanina at all ; in any case the former can have no 

 claim, as the name had previously been used for a genus of Crustacea, as 

 has been pointed out by Morch. 



The fact of the name Nanina having been employed by Risso in 1826 

 is I consider of no importance, as it has long ago been pointed out that he 



