24 PALUDINIDZ. 
It inhabits slow rivers, canals, and ponds as far north 
as Lancashire and Yorkshire. It is often found coated 
with confervoid, which can easily be removed by hot 
water and soap applied with a soft nail-brush. Both 
this and the following species are viviparous. 
2. P. vivipaRA (producing young alive). 
Conical, but more oval than last species. Not so glossy 
as P. contecta; lighter in colour, and more solid. Whorls 
six and a half; swtwre not so deep as P. contecta; wmbilicus 
none ; operculum moderately thick. 
With the exception of one locality in Scotland (near 
Moray Firth) this species is found within the same 
limits as P. contecta. The two species may be dis- 
tinguished by the following characteristics :— 
P, CONTECTA. P. VIViIPABRAS 
Conical. More oval. 
Rather glossy. Not so glossy. 
Dark green. Light greenish yellow. 
Suture very deep. Not so deep. 
Umbilicus distinct. Umbilicus none. 
Texture thin. More solid. 
Apex sharp. Apex blunt. 
Var. I. unicolor. Without bands. 
Var. II. atro-purpurea. With dark purple mark- 
Ings. 
