26 BULLETIN 186, UNITED STATES NATIONAL MUSEUM 



growth after cessation of the rains ; such incendiarism may result in 

 damage to the vegetation of a wide area. Many birds collected in 

 winter have the light portions of the plumage more or less discolored 

 by contacts with charred wood and leaves, a fact that must always 

 be taken into account by the taxonomist. 



ACKNOWLEDGMENTS 



It would be difficult indeed to give fair credit to the numerous in- 

 dividuals who have aided me during the more than 15 years that have 

 passed since I first began the study of Thai ornithology. Perhaps 

 first credit is due Charles H. Rogers, curator of the Princeton Museum 

 of Zoology, to whom I am indebted for financial assistance in the 

 earliest period of my collecting, and to the authorities of the United 

 Stales National Museum for similar subvention during the years 

 1935-1937. For the gift of specimens, many of great importance, my 

 thanks are due almost countless friends in Thailand, both Thai and 

 European; among them I recall at once Hilda Cuniff Pontius, S. T. 

 Queripel, W. Leigh Williams, C. J. Aagaard, T. W. Bevan, A. R. 

 Buchanan, and the teachers and students of the Prince Royal's College. 

 For encouragement and moral assistance in my work I am indebted 

 to the late Dr. A. F. G. Kerr and other members of the Thailand Re- 

 search Society (Siam Society) ; to the members of the Siam Mission 

 of the Presbyterian Church in the U. S. A. (who ever received me 

 hospitably in my travels throughout the Kingdom) ; and particularly 

 to Dr. and Mrs. William Harris of Chiang Mai, from whom I received 

 every opportunity to carry on my favorite studies. 



Special mention must be made of the faithful and cheerful services 

 rendered me by my collector, L. K. A. Charles (Charlie Tan), his 

 assistant, Xai Wan, and our cook-boy, Xai Sang. 



For the opportunity to visit the museums of Europe and there to 

 examine Thai materials. I am indebted to the American Association 

 of Museums for a grant-in-aid and to the trustees of the Walter Rath- 

 bone Bacon Traveling Scholarship for a similar grant. To my wife, 

 Stella Leche Deignan, I am indebted not only for encouragement in my 

 work but. also for many hours spent in painstaking copying of data 

 from the registers of the museums visited. 



Ornithological material has been courteously placed at my disposal 

 by the authorities of the following institutions: 



1. Princeton Museum of Zoology. Princeton, N. J. 



2. Academy of Natural Sciences of Philadelphia. Philadelphia, Pa. 



3. Museum of Comparative Zoology. Cambridge. Mass. 



4. American Museum of Natural History, New York, N. Y. 



5. Chicago Natural History Museum. Chicago, 111. 



