62 RISSOIDiE. 



Genus PACHYDROBIA, Crosse and Fischer. 



J. de C. XXIV, 1876, type P. paradoxa. Or. and F. ; genus of Fam. 

 Rissoidce, fide Martens ; fide Poirler, J. de C. 1881, belongs to the Hydro- 

 hincB, next allied to Q-illia. 



1. Pachydrobia parva. 



Pachychilus parvus. Lea, P. Ac. Nat. Sci. Philad. 7 III, 1856, Siam ; = 

 Melania crassilabrum, Reeve, Icon. 1860 ; = Paludomus cyanostonms, 

 Morelet, J. de C. 1864, Siam. 



4 Cambodia; ex c. A. Morelet, Esq. 



2. Pachydrobia paradoxa. 



Paeliydrobia paradoxa, Crosse and Fischer, J. de C, 1876, Cambodia. 



1 Locality ? ; ex " LiiinEea." 



Gemis HEMISTOMIA, Crosse. 



J. de C. 1872, type Hemistomia caledonica, Crosse. 



1. Hemistomia caledonica. 



Hemistomia Caledonica, Crosse, J. de C. 1872, near Noumea, long. 2\, diam. 

 f mil. 



2 New Caledonia; ex c, P. Bouvier, Esq. 



Genus TRICULA, Benson. 



Calcutta J. Nat. Sist. 1842, type T. montana, Benson ; fide Stimpson, 

 Stoliczka and Blanford, belongs to Fam. RissoidcB. 



1. Trieula montana. 



Triciila montana, Benson, Calc. J. Nat. Hist. 1842, and Ann. Mag. 1862, 

 Bhimthal, at 4,000 fit., Kumaon ; Con. Indica, pi. 155, fig. 1. 



10 Nynee Thai ; coll. Dr. F. Stoliczka. 

 7 Bhimthal [? typical] ; ex c. Asiatic Society, Bengal. 



var. curta, nov. 



2 Jhiri Valley, at 3,000 feet [N. Cachar] ; coU. Colonel H. H. Godwiu- 

 Austen. 



Genus BAIKALIA, von Martens [emend.']. 



Jahrb. Mai. Oes. 1876, fior Limnorea, Dybowski, 1878 \jiot of Leach, cf'c.)] 

 type B. angarensis, Gerst. ; sect. = LiobaiJcalia, Martens, Jahrb. 1876, 

 type B. stiedae, Dyb. ; sect, = Dybowskia, Dall, P. B. S. 1876, type B, 

 ciliata, Dyb. 



