(daylength) to migration by Rowan (1925, 1926) and many 

 subsequent studies (Wolfson 1940, 1945; Marshall 1961; King, 

 Barker and Farner 1963; King and Earner 1963; King 1963; Farner 

 1955, 1960; and Farner and Mewaldt 1953). These studies have 

 become ever more deeply involved in the intricate relationships 

 between photoperiod, endocrine interactions, gonad development, 

 fat deposition, and migratory unrest. They add to our knowledge of 

 the mechanisms that regulate the migratory behavior we observe. 



12 



