VIII INTRODUCTION. 



It is believed that this bibliogi'apliy will materially lighten the 

 labors of everyone engaged in the study of American birds or of the 

 problems of geographical distribution. 



Since Mr. Sclater is not an "American naturalist" in the same 

 sense as the others whose bibliographies have already been published, 

 the present work is not included in the series of "Bibliographies of 

 Auierican Naturalists." He is, however, in another and a broader 

 sense, one of the most eminent and prolific of American naturalists. 



The plan adopted in the present volume is essentially different in 

 its entirety from any previously used, although many of its features 

 are familiar. The method of citation is essentially that of Coues, but 

 the annotations to the titles are made as brief as j)ossiblo. The object 

 of such annotations is understood to be simply to describe each paper 

 so that a person consulting the bibliography can determine mthout 

 further research whether the paper cited is one which he needs to 

 consult. The customary practice of analyzing the paper and enumer- 

 ating under its title all the species, genera, and families which it 

 describes is not followed. It is thought that a much more satisfac- 

 tory plan has been adopted, namely, that of combining this enumer- 

 ation of species with the alphabetical index, so that a person desiring 

 an exact reference for use in synonymy, or indeed for immediate use 

 in consulting the literature, can find in one alphabetical series all the 

 names for which the author is responsible, each accompanied by an 

 exact statement of j^lace of description, the locality of the specimen, 

 and the place where the type is to be found. 



A separate list of species figured, with an exact bibliographical 

 citation for the plate and the page related to it, is also given. The 

 reason for including a separate list of the species figured is obvious, 

 since a large number of Mr. Sclater's figures relate to forms not for 

 the first time described by him. 



Much care has been given to the typography of this bibliograj)hy, 

 with the purpose of securing compactness as well as clearness. The 

 material here included, if printed in the same style as the bibli- 

 ographies previously issued by the Museum, would have occuj)ied 

 at least four times the space. Notwithstanding this compactness of 

 typography, the arrangement of the matter and the contrasts secured 

 by the choice of type and by the system of spacing and indentation 

 adopted has, it is believed, produced a page which is clearer and 

 easier of reference than any i^reviously used, at all events in the pub- 

 lications of the Museum. 



Special acknowledgment is due to Mr. George Arthur Doubleday, 

 clerk in the library of the Zoological Society of London, by whom the 

 titles have been copied and arranged. Mr. Charles W. Richmond, of 

 the National Museum, has done excellent service in reading proof and 

 verifying the citations. 



