1902.] NATURAL SCIENCES OF PHILADELPHIA. 115 



REVISION OF JAPANESE VIVIPABID.E, WITH NOTES ON MELANIA 

 AND BITHYNIA. 



BY HENRY A. PILSBRY. 



My work on these groups has been based largely upon material 

 supplied by Mr. Y. Hirase, of Kyoto, Japan. 



VIVIPABIDJE. 



The Viviparidce of Japan, so far as their appearance in the field 

 of literature is concerned, are involved in mind -destroying chaos. 

 This has been due partly to the intrinsic difficulty of the subject, 

 but chiefly to a failure on the part of authors to correctly identify 

 the older Oriental species. Mr. T. Iwakawa, 1 of Tokyo, has pub- 

 lished a lucid essay upon the subject, in which the natural divisions 

 or species are for the first time correctly set forth. Owing, how- 

 ever, to the fact that he used the names for the species given by 

 Kobelt 2 (as there is probably no library in Japan sufficient for the 

 verification of the German author's statements), the nomenclature 

 adopted by Iwakawa requires revision. This implies no criticism 

 of the Japanese naturalist's admirable essay. The source whence his 

 nomenclature was drawn was tainted; but the names aside, his grasp 

 of the facts of nature was sound. 



Pseudo -Japanese species. 

 In my opinion, the following species do not occur in Japan : 



Paludina oxytropis Benson, Journal of the Asiatic Societ}^ of Bengal, 

 v, 1836, p. 745, type locality Sylhet. Figured in Conchologia 

 Indica, PI. 76, fig. 5, and Conch. Iconica, fig. 9. 



-f- P. pyramidata v. d. Busch in Philippi, Abbildungen, etc., I, p. 

 113, PI. 1, figs. 3, 4 (1844). Type locality, Bengal. 



Paludina ingallsiana Lea, Proc. Acad. Nat. Sci., 1856, p. 110. Fig- 

 ured in Observations on the Genus Unio, etc., XI, p. 74, PI. 22, 

 fig. 9. Type locality, Siam. Not P. ingallsiana Reeve ! 



I am satisfied that those who will compare authentic specimens of 



1 Notes on the Paludina-species of Japan, in Annotationes Zoologies 

 Japonenses, I, Part 3, pp. 83-92, PI. V, 1897. 



2 Fauna Molluscorum Extramarinorum Japonic^, Frankfurt, 1879. 



