THE MIGRANT SHRIKJ-.. 



way to account for the considerable diversity which we find in specimens, is 

 simply to recognize this state as a meeting ground of two forms which have 

 attained their maximum differentiation elsewhere, — ludovkianus in the South, 



Photo by tin- Autho 



THE SHRIKE'S FORTRESS. 



and excubitorides in the West — and without attempting to assign subspecific 

 value to the various phases as they appear. Hence, however we may regard, from 



