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2. Description of Thirteen New Species of Paludinacea 

 from Ceylon, in the Collection of Hugh Cuming, Esq. 

 By H. Dohrn. 



Genus 1. Paludina. 



1 . Paludina ceylonica. Testa ovato-conica, perforata, soli- 

 diuscula, viridis, versus apicem fuscescens ; spira magisminusve 

 elevata, exserta ; anfractus convexi, ad suturam et basin obso- 

 lete, medio acute carinati; spiraliter et longitudinaliter striata; 

 sutura simplex, impressa ; apertura ovata, intus alba, peri- 

 stoma subincrassatum, reflexiusculum, nigrum. 



Long. 21, lat. 16 ; apert. long. 12^, lat. 9 mill. 



Genus 2. Bithynia. 



1. Bithynia stenothyroides. Testa ovata, tenera, alba vel 

 fulva, pellucida, nitida ; anfractus 4-5 convexiusculi, ultimus 

 efflatus, ventricosus, ad basin leviter carinatus, antice descend- 

 ens ; sutura simplex ; apertura oblongo-ovata, parum coarctata, 

 ad basin acuta, alba. Operculum oblong o-ovatum, testaceum, 

 crassum, concentrice striatum. 



Long. 5^, lat. 4£ ; apert. long. 3, lat. 2 mill. 



Ceylon, Nilgherries. 



This species has some characters of Stenothyra. The last whorl 

 is unusually great, the mouth somewhat contracted, but the general 

 aspect is that of Bithynia. 



2. Bithynia inconspicua. Testa oblongo-conica, tenera, alba 

 vel fulva, pellucida ; spira acuta ; anfractus 4—5 convexiusculi, 

 sub lente leviter longitudinaliter striati ; apertura oblonga. 

 Operculum testaceum, concentricum. 



Long. 5, lat. 3^ ; apert. long. 2\, lat. \\ mill. 



In shape nearly allied to our common B. tentaculata, but differ- 

 ing in size ; the whorls are rounder, broader in proportion to the 

 height, and flatter than in B. orcula, Bens., and the whole form is 

 more conic. 



Genus 3. Paludomus. 



1. Paludomus fulguratus. Testa oblongo-ovata, tenera; 

 spira elevata, apice obtuso, leviter longitudinaliter et spiraliter 

 striata, Icete olivacea, fusco fulgurata, ad suturam impressam 

 fusco fasciata ; anfractus quatuor convexi, supra medium ob- 

 solete carinati ; apertura oblonga, simplex, albida, lineis fuscis, 

 pellucentibus. Operc. 1 



Long. 16, lat. 13 ; apert. long. 11, lat. 6 mill. 



2. Paludomus nasutus. Testa solida, oblongo-conica, apice 

 acuto, nigrescens, versus apicem albicans, ad suturam linea 

 valde impressa distinct a, obsolete decussata ; anfractus quatuor 



