116 Records of the Indian Museum. [Vol. XIV, 



The type-specimen of the race (belonging to the large foim) is No. 

 M. 11155/2 in the collection of the Zoological Survey of India. 



Genus Paludomus, Swain son. 



This genus is represented in our collection by two small shells only. 

 They were found near the town of Yawnghwx. The genus, though 

 occasionally found in still water, is usually an inhabitant of small 

 streams and never lacustrine. 



Paludomus ornata, Benson. 



1856. Paludomus ornata, Benson, Ann. Mag. Nat. Hist., (2) XVII, p. 496. 

 1876. Paludomus ornata, Hanley and Theobald, cp. cit., pi. cviii, fig. 8. 



The two shells of this species in our collection are very small, the 

 larger being only 15 mm. in length. They are covered with a thin 

 but somewhat dense layer of calcareous matter, which partly conceals 

 the parallel grooves running round the top of the whorls, and gives the 

 shell a dull appearance. When this calcareous matter is removed, 

 however, the natural colouration and sculpture of the surface appear 

 uninjured. 



The shells were found living on a muddy bottom in a small runnel 

 of clear water by the roadside some two miles east of Yawnghwe. 



The species was described from Upper Burma, but occurs also in 

 Pegu and in the valley of the Brahmaputra. 



Family HYDROBIIDAE. 



1915. Paludestrinidae, Preston,^ op. cit., p. 67. 



A large proportion of the members of this family are lacustrine 

 and it is therefore not surprising that several species are common in 

 the Inle Lake. In Indo-China and China a number of peculiar genera 

 have been evolved, but most of these seem to be peculiar to swift- 

 running water, a type of environment of which w^e had little experience 

 in the Shan States. None of the Indo-Chinese genera, perhaps for 

 this reason, were found in the Inle basin. With one exception, 

 the six species of the family that we found belong to the peculiar genus 

 Hydrohioides, Nevill. This genus was erected, as a subgenus of 

 Bithynia, to include two species, one of which {H. tvrrita, Blanford) 

 we found in a subfossil condition on the He-Ho plain, while the other, 

 the position of which is still doubtful and which has not yet received 

 a name, was from Kach. The named form was described from the 

 Irrawaddi system and is still only known from empty shells, but four 

 other species were found living in the Inle basin and it has been possible 

 to give a description of the operculum, the radula and the external 

 anatomy of three. 



The only other species of the family is assigned provisionally to the 

 genus Amnicola, from the typical forms of which, however, it differs 

 in its calcareous operculum. 



^ Preston's removal of Bithinella {op. cit., p. 66) from the family and its inclusion 

 as a subgenus in Cremnoconchus (fam. Littorinidae) is not explained. 



