PALUDINA. 139 



it would appear that the anxious mother is by no means in 

 haste to rid herself of the care and responsibility of her in- 

 fant offspring. 



The PaludincB inhabit fresh-water streams. They have 

 a rather square, lengthened proboscis, with hairy-ended ten- 

 tacles, which are thickened at the bases by the union with 

 them of the eye-pedestals ; they have a triangular foot, on 

 the end of which is placed a horny operculum; this opercu- 

 lum is oval, and formed of successive layers round a central 

 nucleus [concentric operculum) ; the tongue is short, armed 

 with denticles. The shell is rather top-shaped, with a high 

 spire, composed of rounded, gradually -increasing whorls; 

 the aperture oval, having an uninterrupted edge ; a smooth, 

 thin epidermis covers the exterior. 



P. Lister I (commonly known as P. mvAjmrd) has the shell 

 rather short, with a large perforation behind the mouth ; 

 whorls darkly three-banded, very full and rounded; 

 the mouth has a rather thickened ledge. The animal 

 is brightly speckled with greyish, yellow, and brown, 

 with a large mantle ; on the whole, of a golden hue. 

 P. vivipara (known as P. fasciata) has a rather more oval 

 shell, with the whorls not so rounded and separate, 

 a smaller perforation, and no doubling of the edge of 

 the aperture. Animal on the whole of a copjiery hue. 



