QUESTIONS. 121 



QUESTIONS IV. 



1. What is the derivation of the terra Cephalopoda ? 



2. Give examples of this class. 



3. What are its distinctive characters ? 



4. What is the habitat of these animals ? 



5. What are their habits ? 



6. Describe the "arms," the "funnel," and the "mantle." 



7. What are the distinctive features of the arms in the Poulpe, 



the Cuttle-fish, the Paper Nautilus, and the Pearly 

 Nautilus ? 



8. How is locomotion effected ? 



9. What cephalopods possess an external shell ? 



10. Describe the external shell, and show how it differs from 



the univalve shell of the Gasteropoda. 



11. What members of this class have an internal shell? 



12. What cephalopods are destitute of a shell? 



13. What is the nature of " cuttle-bone " ? 



14. Describe the "pen" of the calamary. 



15. Describe the internal shell of the Spirulce. 



16. What are Belemnites ? 



17. What are Ammonites ? 



18. W^hat is the nature of the digestive apparatus in this class ? 



19. Describe the "jaws" and the odontophore. 



20. Describe the "ink-bag," and state whether it is possessed 



by all the members of this class. 



21. Describe the heart and circulatory organs. 



22. What are ' ' branchial hearts " ? 



23. What cephalopods are destitute of these organs ? 



24. Does the heart contain venous or arterial blood 1 



25. Describe the breathing organs. 



26. How is respiration effected? 



27. Show that respiration and locomotion are associated in this 



class. 



28. On what principle are the Cephalopoda divided into orders ? 



Name the orders. 



29. Give an account of the nervous system and the organs of 



sight. 



30. What is a Hectocotylus ? 



31. Why are the Pteropoda so called? 



32. Give examples of this class. What is their usual habitat ? 



33. Describe the shell of the Pteropoda. 



34. What is the nature of their digestive apparatus ? 



35. How is respiration effected ? 



36. Explain the term Gasteropoda. 



