PREFACE. 



The scheme of the present work has had to be extended, inasmuch as 

 the author has found it impossible to compress the remainder of the 

 Passeriformes into the space of a single volume, and it has therefore 

 been found more convenient to complete the ' Hand-list ' in five volumes, 

 instead of four, as was originally intended. The continual addition to 

 the number of described species of Passerine Birds has also rendered 

 this course more expedient, in order that the volumes of such a work of 

 reference as the present, should be kept within a reasonable size for 

 frequent consultation. 



It is probable that the fifth and concluding volume will be published 

 iu the course of a few months, as it is already well advanced. 



E. RAY LANKESTEE, 



Director, 

 Natural History Departments, 

 July 13, 1903. British Museum. 



