Continued from outside back cover 
557 Long-term shifts in autumn migration by songbirds at a coastal eastern North American stopover site 
Susan B. Smith and Peter W. C. Paton 
567 Habitat use of the Louisiana Waterthrush during the non-breeding season in Puerto Rico 
Michael T. Hallworth, Leonard R. Reitsma, and Kyle Parent 
575 Spring stopover and refueling among migrant passerines in the Sierra de Los Tuxtlas, Veracruz, Mexico 
David W. Shaw and Kevin Winker 
588 Molt patterns, biometrics, and age and gender classification of landbirds on Saipan, Northern Mariana 
Islands 
Paul RacUey Andrea L Crary, James Bradley, Christina Carter, and Peter Pyle 
595 Parrot behavior at a Peruvian clay lick 
Donald J. Brightsmith and Ethel M. Villalobos 
Short Communications 
603 Vocal repertoire of the Yellow-Faced Parrot {Alipiopsitta xanthops) 
Carlos B. de Araujo, Luiz Octavio Marcondes-Machado, and Jacques M. E. Vielliard 
608 Plasma testosterone concentrations in adult Tree Swallows during the breeding season 
Molly Staley Carol M. Vleck, and David Vleck 
613 First description of the breeding chronology of the White-collared Swift (Strep,oprocne zonaris) in 
Argentina 
Julieta M. Passeggi 
618 Nesting of the Fulvous-breasted Flatbill (Rhynchocyclus Julvipectus) in southeastern Peru 
David Ocampo and Gustavo A. Lotidoho 
624 Hourly laying patterns of the Pearly-eyed Thrasher (Margarops fuscatus) in Puerto Rico 
Wayne J. Arendt 
628 First record of interspecific breeding of Least Bells Vireo and White-eyed Vireo 
Melissa A. Blundell and Barbara E. Kus 
632 Triorchidism in a Hummingbird 
Christopher C. Witt and Emil Bautista 
635 Nest reuse by the Scintillant Hummingbird ( Selasphorus scintilla) 
Emilia Triana and Luis Sandoval 
638 Natal and adult dispersal of Red-eyed Vireos in a large southern Ontario forest 
Benjamin J. Walters and Erica Nol 
641 Evening nest-box departure times of Eastern Screech-Owls 
Werner G. Deuser 
646 Carrion-feeding by Barred Owls ( Strix varia) 
Joshua M. Kapfer, David E. Gammon, and John D. Groves 
650 Ornithological Literature 
Robert B. Payne, Review Editor 
