INTRODUPTION. 7 



Mr. Edward C. Gale and Mr. Horace V. Winchell for the large 

 amount of time which they have given to the carrying out of our 

 common plans; to the Athenaeum Library Board and the Minneapo- 

 lis Public Library for their liberality in providing the literature 

 without which the work would have been impossible and to the 

 many friends of the Academy who have furnished financial aid at 

 a time when they could ill afford to do so. 



In connection with our final paper we shall publish careful meas- 

 urements of all the species of land birds obtained. With the excep- 

 tion of the birds collected by Mr. Moseley no measurements were 

 taken in the field on the birds of the Steere Expedition and many of 

 the length measurements given for them were taken from dry skins 

 and are, therefore, unreliable. With very few exceptions all of the 

 birds collected by the Menage Expedition were measured in the flesh 

 for length and during the past summer a complete and careful se- 

 ries of measurements of more than four thousand specimens has been 

 prepared by Messrs. Lawrence E. Grifiin and Ernest G. Martin of 

 Hamline University, Saint Paul, Minn. We are greatly indebted to 

 both of these young men for the care and diligence with which they 

 carried out this important piece of work. The data furnished by 

 them will enable us not only to furnish for each species average 

 measurements from a large series of specimens but also to ascer- 

 tain the relative amount of individual variation in the representatives 

 of those genera which display a strong tendency to develop local 

 species as compared with other genera which show no such tendency. 

 In addition to the work above mentioned Messrs. Grif&n and Martin 

 gave us much valuable assistance. 



