AVES 437 



that birds are useful need not obscure the fact that they are 

 interesting. 



444. Special Topics for Investigation in Field and Library. 



1. Enumerate the special structural features which seem to fit birds for suc- 

 cessful flight. Compare different birds as to these features? What are the 

 different modes of flight? Compare the flight of the buzzard, the woodpecker, 

 the quail. What is the action of the wings in flying? Of the tail? What is the 

 effect of clipping one wing? Why? The rate of flight in different species of birds. 



2. Study the group of birds from the point of view of their social and gregarious 

 instincts. Are any solitary? Do any have varying social habits during different 

 seasons? 



3. Make a general study of the migrations of birds, collecting the facts as to 

 range, time, supposed causes, the effects on the species and its geographical distri- 

 bution, the degree of exactness in routes and the place of return. 



4. Make a special study of the birds of the locality in which you are. Are 

 there permanent residents? Summer residents? Winter residents? Migrants 

 (those which stop only for a short time in the spring or autumn as they pass from 

 south to north or the reverse)? Keep a record from year to year of the earliest 

 dates at which migrating species are seen in your locality. 



5. What diversity is there in the mating habits of birds? Are any mono- 

 gamous? Polygamous? What are the mating and nesting habits of the cuckoo? 



6. Make a report as to the nest-building habits of selected species of birds. 

 How do the nests differ in location, in mode of formation, in perfection? Is there 

 any relation between the character of the nest and the degree of development of 

 the young when hatched? What range of variation in the number of eggs? In 

 the mode of incubation? The period' of incubation? Care of the young after 

 hatching? 



7. Compare the vocal powers of birds with that of vertebrates hitherto studied. 

 Compare various types of birds as to the range and character of their notes. How 

 are the notes of birds related to their states of mind ? Which are more vocal, the 

 males or the females? What explanations are offered for this? 



8. What is the history of the English sparrow in this country? What are its 

 habits? How do you account for its rapid spread? 



9. Make a special study of the local distribution of the species of birds known 

 to occur in your vicinity. Which prefer the meadows? The marshes? The 

 streams? The woodlands? Do the different species nest in the same regions in 

 which they feed? 



10. The relation of selected species of birds to man. Are they helpful or harm- 

 ful to his interests? Has he been helpful or harmful to them? 



