VARIATIONS IN HYLOCICHLA USTULATA — BOND 



377 



Magnification of X 10 in a binocular microscope was used in exam- 

 ining feathers for wear and abrasion. 



For their many helpful comments and suggestions while the study 

 was in progress I would like to express my appreciation to Dr. John 

 W. Aldrich, Dr. Harry C. Oberholser, and Mr. Herbert G. Deignan. 

 To Dr. Alexander Wetmore I am particularly indebted for the time 

 and effort he has spent in helping me revise the final manuscript. 



H. u.ustulata 

 H.u.oedica 

 H.u.almae 

 H.u.swainsoni 



Figure 1. — Ranges of the subspecies of Hylocichla ustulala. 



Dr. Herbert Friedmann allowed me to use specimens under his care 

 in the U.S. National Museum collection. 



The following persons loaned specimens: Dr. Ira N. Gabrielson; 

 Dr. Kenneth C. Parkes, Cornell University; Dr. W. Earl Godfrey, 

 National Museum of Canada, Geological Survey Museum of Canada, 

 and the Victoria National Museum. 



I also wish to express my appreciation to Dr. Brina Kessel, Univer- 

 sity of Alaska, and to Dr. Allan R. PhiUips of Mexico City for their 

 cooperation. 



