142 UNIVALVES. 



QUESTIONS ON THE UNIVALVE 

 SHELLS. 



1. What are the parts of an univalve shell ? 



2. Give a description of each part, with the 

 derivation of the terms. 



3. How is the genetic character of univalve 

 shells determined ? 



4. How is the specific character of univalve 

 shells determined ? 



5. Give a list of the genera of univalve shells. 



6. Name those which have regnlar spires. 



7. Name those without spires. 



8. Which genera seem to connect the shells 

 with spires, and those without ? 



9. What shells have longitudinal apertures ? 



10. Which shells are canaliculated, and which 

 entire ? 



11. Which of the univalve shells resemble 

 each other ? Describe their points of resemblance 

 and also in what respect they differ. 



12. In what respect do the shells of warm 

 climates differ from those of colder regions ? 



13. What is the generic character of the 

 Cone ? and what its distinguishing mark ? 



14. What remarkable instinct is exhibited by 

 the animal of the Cone ? 



15. Where are Cones found ? 



16. What is the generic character of the 

 Cypraea, and what its most distinguishing mark ? 



17. What is there remarkable in the manner 



