BLA.NFORD : NOTES ON ARIOPHANTA AND EUTEECTA. 243 



(torn, cit., 1899, pp. 123-127), and showed that, despite some small 

 differences, chiefly in the mantle-lobes, both belonged to the same 

 generic type {Nilgiria) and agreed in all important points with 

 Ariophanta. More recently specimens of II. Gardeneri and H. ganoma, 

 for which, beautifully preserved in formaline, we are indebted to the 

 kindness of Mr. Oliver Collett, have been examined by Godwin- Austen, 

 who informs me that they must be referred to the same genus as 

 H. Tranquebarica (H. semirugata) and H. bistrialis. H. ganoma is 

 a mere colour variety of H. Juliana. 



The only conclusions at which I can arrive are that Xestina and 

 Nilgiria are identical, and the former name is of course the older. 

 The group to which these names have been applied is neither a genus 

 nor subgenus, but merely a section of Ariophanta, distinguished by 

 a character which is not of generic importance. The difference 

 in the shells between the homy, globose, thin-lipped, and narrowly 

 perforate Ariophanta intumeseens, and the solid, depressed, thick-lipped, 

 and openly umbilicated A. thyrcus, or between A. l&vipes and A. cysis, 

 all belonging to the typically sinistral forms of the genus, are quite 

 as great as those between either of them and the dextrally wound 

 A. semirugata or A. bistrialis. 



In a former paper (Proc. Mai. Soc, vol. iii, 1899, p. 282), I gave 

 a list of the typical sinistral Ariophantce known to me from Peninsular 

 India. Further examination of Colonel Beddome's splendid collection 

 and of my own has induced me to reduce one of the species named to 

 subspecitic rank, and to add one more species and two additional 

 subspecies. 



With regard to the forms arranged as subspecies, not only is it 

 impossible, I believe, to lay down any rule by which a species can 

 be distinguished from a subspecies, but I fail to recognize any real 

 difference between them. Subspecies, for the present, I regard as 

 forms sufficiently well marked to require a separate name, but which, 

 owing to the presence of intermediate gradations, cannot be distinguished 

 from each other. Species are forms which, so far as our present 

 knowledge extends, are not connected by intermediate varieties, 

 although in some cases the existence of such links may be suspected. 



The following lists of species of Ariophanta and Evplecta inhabiting 

 Cisgangetic India and Ceylon are drawn up from the comparison of 

 materials in the British Museum and in the collections of Colonel 

 Beddome, Mr. J. H. Ponsonby, and Mr. E. R. Sykes, supplemented 

 by those obtained by my brother, the late Mr. H. F. Blanford, and 

 by myself. I am much indebted to the gentlemen mentioned for 

 assistance in the work, and also to Mr. E. A. Smith for most valuable 

 aid with the British Museum collections. To Mr. Oliver Collett and 

 Dr. Thurston, of Madras, I am under much obligation for specimens 

 very kindly sent ; and of course the work has been only possible in 

 consequence of my having the advantage of Colonel Godwin- Austen's 

 advice and aid. 



