ACKNOWLEDGMENTS 



Free and unacknowledged use has been made of the many 

 excellent texts and original papers on the subject. Few con- 

 clusions, even minor ones, have been contributed by a single 

 worker; and all of the older results have now become common 

 property, a part of our scientific heritage. Further, complete 

 acknowledgment in the text would be confusing to more ad- 

 vanced students than those for whom this text is designed. 



The author owes thanks to his colleagues who helped plan the 

 course, and who assisted in re-shaping the outline and content 

 of this book. I am particularly grateful to Dr. H. A. Charipper 

 who read Parts I and II, and to ^Ir. R. T. Kempton who read 

 the entire manuscript. Dr. H. E. AVood, 2nd., read Part III, 

 and Mr. Everett Lyne the entire book. 



The drawings for Chapter XV were made by Dr. Florence 

 D. Wood. Mr. Anthony Barbanera illustrated Chapters YIII, 

 XI, XII, XVII, and XVIII, and made some drawings for other 

 chapters. 



In the preparation of the manuscript for publication, and in 

 reading the proofs, the author has had the assistance of Miss 

 Lillian Fuellhart, Miss Charlotte Rowe, and Miss Katharine 

 Twichell; and of his assistants, Robert H. Ringewald, Thomas 

 G. lerardi, James G. Meyers, and Herman Littman. Dr. John 

 J. Schoonhoven edited the glossary. 



]\Iany of the drawings are from the publications of, or mate- 

 rial in, the American Museum of Natural History. Several of 

 the birds were copied from paintings; many of the natural history 

 and skeletal drawings were made from specimens. The author 

 is grateful for the permission to work at the ^luseum. 



Although the manuscript was carefully edited by men who 

 have had long experience in teaching anatomy, numerous minor 

 errors have undoubtedly escaped their attention. Wherever there 

 was a disagreement as to method of treatment or the inclusion 

 of material it was necessary for the author to depend upon his 

 own judgment. For any errors of fact, and for the general poli- 

 cies, the author takes entire responsibility. 



