14 CATECHISM OF CONCHOLOGY. 



area, or anterior slope, and areolo, or posterior 

 slope. 



A. The first is that side of the beaks, or that 

 space in which the ligament is situate. The 

 second, of course, the other side of the beak. 



Q. What are the apices or beaks ? 



A. They are the tips or extreme parts of the 

 umbones or bosses, as they are termed by Con- 

 chologists, or rather of that part where the two 

 shells meet. 



Q. What are the Auriculae, or ears ? 



A. Angular projections, either on one or on 

 both sides of the beaks. 



Q. Have the goodness to describe the base of 

 a shell. 



A. It is that part of the margin of the shell 

 which is immediately opposite to the beak or 

 summit. 



Q. Where is the cavitas or cavity ? 



A. The inside of the shell. 



Q. What is meant by the term margin ? 



A. It is the edge of the shell : anterior, the 

 space in which the ligament is situated ; posterior? 



