62 RISSOIDA. 
Genus PACHYDROBIA, Crosse and Fischer. 
J. de OC, XXIV, 1876, type P. paradoxa, Cr. and F.; genus of Fam, 
Rissoida, fide Martens ; fide Poirier, J. de C, 1881, belongs to the Hydro- 
bine, next allied to Gillia. 
1. Pachydrobia parva. 
Pachychilus parvus, Lea, P. Ac. Nat. Sci. Philad. VIII, 1856, Siam; = 
Melania crassilabrum, Reeve, Icon. 1860; = Paludomus cyanostomus, 
Morelet, J. de C. 1864, Siam. 
4 Cambodia; ex c. A. Morelet, Esq. 
2. Pachydrobia paradoxa. 
Pachydrobia’paradoxa, Crosse and Fischer, J. de C., 1876, Cambodia. 
1 Locality ?; ex “ Linnea,” 
Genus HEMISTOMIA, Crosse. 
J. de C. 1872, type Hemistomia ealedonica, Crosse. 
1. Hemistomia caledonica. 
Hemistomia Caledonica, Crosse, J. de C. 1872, near Nowméa, long. 2k, diam. 
ae 
iz mil. 
2 New Caledonia; ex c. P. Bouvier, Esq. 
Genus TRICULA, Benson. 
Calcutta J. Nat. Hist. 1842, type T. montana, Benson; fide Stimpson, 
Stoliczka and Blanford, belongs to Fam. Rissoide. 
1. Tricula montana. 
Tricula montana, Benson, Cale, J. Nat. Hist. 1842, and Ann. Mag. 1862, 
Bhimthal, at 4,000 ft., Kumaon ; Con. Indica, pl. 155, fig. 1. 
10 Nynee Thal; coll. Dr. F. Stoliczka, 
7 Bhimthal [? typical]; exc. Asiatic Society, Bengal. 
var. curta, nov. 
2 Shiri Valley, at 3,000 feet [N. Cachar] ; coll. Colonel H. H. Godwin- 
Austen. 
Genus BAIKALIA, von Martens [emend.]. 
Jahrb, Mal. Ges. 1876, for Limnorea, Dybowski, 1878 [not of Leach, &§c.)] 
type B. angarensis, Gerst.; sect. = Liobaikalia, Martens, Jahrb. 1876, 
type B. stiedae, Dyb.; sect, = Dybowskia, Dall, P, B.S. 1876, type B. 
ciliata, Dyb. 
