6 tJ. S. BUREAU OF FISHERIES 



who worked upon it from time to time, as their other duties per- 

 mitted, until 1925, when they were joined by the junior author, who 

 thereafter gave most of his time to the work until its completion. 

 The senior authors also have devoted much of their time to it since 

 1925. 



During the progress of the work the authors have endeavored to 

 consult and utilize every record bearing on the fish fauna of America. 

 In addition to this they have received invaluable assistance and sug- 

 gestions from virtually every present-day student of American fishes, 

 among whom special mention should be made of the late Dr. Charles 

 Henry Gilbert and Prof. John Otterbein Snyder of Stanford Uni- 

 versity, Dr. William Converse Kendall of the United States Bureau 

 of Fisheries, Dr. Carl Leavitt Hubbs of the Univei-sity of Michigan, 

 George Sprague Myers of Stanford University, Barton Appier Bean 

 of the United States National Museum, William Francis Thompson 

 of the International Fisheries Commission, Dr. Arthur W. Henn of 

 the Carnegie Museum, John Treadwell Nichols and Dr. E. W. 

 Gudger of the American Museum of Natural History, and many 

 others. To all these we express our indebtedness and grateful 

 appreciation. For clerical assistance of one kind or another, par- 

 ticularly in looking up and verifying references, we are greatly 

 indebted to Miss Jessie E. Drayton, Harry J. Christoffers, and 

 Henry D. AUer, of the United States Bureau of Fisheries. Without 

 the assistance so generously given by these and others, this memoir 

 could hardly have been completed. 



David Starr Jordan. 



Barton Warren Evermann. 



Howard Walton Clark. 

 Stanford Universiti, 



California Academy of Sciences, 



January 4, 1928. 



