GLOSSARY. 109 



nemordlis, inhabiting groves. 



Neritidce. A Family of mollusks. 



Neritina. The name of a genus. 



nitens, shining. 



nitidulus, rather shiny. 



nitidus, shiny. 



nucleus i the tip of the spire of a univalve shell. 



0. 



oblonga, oblong. 



obscurus, hidden. 



obtusalis, blunt. 



obvoluta, wrapped up. 



ochrdcea, yellow. 



operculated, furnished with an operculum. 



operculum, a covering or lid. A hardened plate attached 

 to the foot of the animals of many univalves, which 

 closes like a door or lid when the animal withdraws 

 into the shell. 



Order. In natural history the subdivision of a Class. 



orifice, a hole. 



orndta, ornamented. 



ovdlis, oval. 



oviparous, producing eggs. 



ovoviviparous, producing eggs which are hatched in- 

 ternally. 



P. 



pdllida, pale. 



Paludvna, inhabiting marshes ; the name of a genus. 



PaludinidcB. A Family of mollusks. 



paliistris, living in marshes. 



