>*New Theories: 



A Body-weight : Egg- weight Index. 

 B Temperature and Ascent Theory. 



* Bird temperature. 



** Rapidity of metabolism or "swiftness of life." 

 ***Temperatures, incubation lengths, and taxo- 



nomic position. 

 **** Collateral evidence. 



6 Present data and this new theory. 

 7 Usefulness of new theory. 



8 Does correlation of temperature and incubation length 

 benefit species? 



9 Data need for further study of this problem. 



10 Conclusions 

 A Minor. 

 B Major. 



11 List of incubation periods. 

 12 Bibliography. 



