224 EXPLANATION OF TERMS. 



Marine. Belonging to the sea ; from mare, the 

 sea. 



Multilocular. Having several chambers, from 

 mult us many, and local um* a little 

 chamber. 



Operculum or Lid. A plate or door, with which 

 some species close the aperture of their 

 shells, from oper io } I cover. 



Orbicular. Quite round, or circular. 



Parallel. Running in the same direction as 

 another thing, being always at the same 

 distance from it ; from the Greek Trap a 

 (para) by the side of, and aXXyXw (alle- 

 lon) each other. 



Pellucid. So clear that the light is seen through ; 

 from per, through, and lu#, light. 



Pervious. Easily passed through; from per, 

 through, and via, a way. 



Plicated. Folded or plaited ; from plica, a fold. 



Punctured. Pricked or marked with small dots ; 

 from punct urn, a point or dot. 



Patulous. Lying open or spreading ; from pat 

 ere, to lie open. 



Quincunx. Disposed alternately as in rows of 

 spots, when the spots of each row are 

 opposite to the space between two spots 

 of the next row ; from quince, five and 

 unx, ounce, as the weight representing 

 five ounces was stamped thus :.: 



Rotatory. Like a wheel ; from rota, a wheel. 



