30 



Scientific name. 



Glauca, 



Raarusa, 



Pellucida, 

 Fragilis, 



Planata, 

 Lutraria, 



DIVISION II. Shell ovate, oblong. 

 Family 1st. Closed at both ends. 



Locality. 

 Spain and Britain. 

 Med., Nicobar. 



Scientific name. 

 Egyptica, 



Locality. 

 Red Sea. 



Family 2d. Gaping at the anterior end. 



Listeri, Britain. 



Guinea. 

 Nicobar. 



Family 3d. Gaping at both ends. 

 Hians, 



Tranquebar, Britain. 

 Britain. 



Britain. 



