OF ORNITHOLOGY 139 



3. European Birds found in North America. 



4. North American Birds found in South America. 



5. South American Birds found in North America. 



6. Where shall we draw the Line between the North and 



the South American Avi-fauna ? 



7. The Avi-fauna of Central America and its Boundaries 



North and South. 



8. The Birds of the West Indies. 



9. The Winter Residence of our North American Birds. 



10. In the Nests of what Birds does the Cow Bird, Molo- 



ihrus ater, lay her eggs and how many ? 



11. Double-yolked Eggs. 



12. The Colors of Birds Eggs and how produced ? Is there 



a Law regulating them ? 



13. Changes of Habits amongst Birds. 



14. A Theory of Albinism. Enumeration of Species. 



15. A Theory of Melanism. Enumeration of Species. 



16. A Theory of Bird Growth. (Size in Old and Young, in 



Male and Female.) 



17. Pneumacity in Birds. [This could be made a very inter- 



esting subject for Original investigation]. 



18. Coloration and Ornamentation in Birds. 



19. The Theory of Flight in Birds. 

 '20. Birds that Sing in the Night. 



21. Birds that Sing on the Nest. 



22. Curiosities of Bird Architecture. 



23. -Causes of Decrease (or Increase, if observed) in the 



Abundance of Certain Species of Birds in different 

 Years in the same Area. 



24. Extinct Birds. 



25. Faunal Areas. 



26. Early and Late Arrival and Departure of Birds (in any 



given Locality) and probable Causes. 



27. Variation in Size in Eggs of the same Species. 



28. Derivation of Names from Foreign Languages. 



Any or all of these Topics can be enlarged indefinitely. 



