6 Preface. 



This subfamily, we find, contains two sections: Section i, having the 

 tail feathers not stiff and pointed, and Section 2, tail feathers stifT and 

 pointed. Our duck has stiff, pointed tail feathers, and therefore be- 

 longs in Section 2. Section 2 contains two species, one having 

 whole front of head and cheeks black, the other, with sides of head 

 more or less white. As our duck has a patch of white on the side of 

 the head, it must therefore be the Ruddy Duck, Erismatura jamai- 

 censis, No. 66, the number indicating its location in the main body 

 of the work, where the different species and subspecies are treated 

 in their proper order and more amplified descriptions of the various 

 plumages are given. 



All measurements of birds are given in inches and fractions of an 

 inch. The diagrams on page 20 will illustrate how a bird should be 

 measured, and the chart (page 12) will be useful to the student 

 of ornithology who may not be familiar with the technical terms used 

 in describing birds. Such terms as primaries, axillars, carpus, etc., 

 should be learned at once. It is customary to indicate the sexes by 

 the signs of Mars and Venus; the male, of course, being given that 

 of Mars, 6^, and the female, Venus, 9 . 



In preparing the present work I have made free use of previous 



put)lications by various authors, due credit being given in such cases, 



and I wish to express my acknowledgments and thanks to Mr. Isaac 



E. Hess, Mr. Ruthven Deane, Mr. Frank M. Woodruff, Mr. R. Magoon 



Barnes, Mr. Girard A. Abbott, Mr. H. K. Coale, Mr. J. Grafton Parker, 



Mr. B.. T. Gault, Mr. H. S. Swarth and Mr. John F. Ferry, for many 



notes, and records, and to Mr. Wni. J. Gerhard, Assistant Curator 



of Entomology, for valuable assistance in reading and correcting 



the proofs. 



C. B. C. 



