IV PREFACE. 



more are only known to us by their dried skins, their 

 beaks, and their feet. These organs, although affording 

 valuable help towards a preliminary arrangement, are, 

 as we are now beginning to discover, by no means 

 sufficient to establish the correct place of any bird in 

 the Natural System. 



It may also be added, for the benefit of those who 

 are not well qualified for the examination of the above- 

 named structures, that much still remains to be done 

 in the study of the habits and nidification of exotic 

 species. Field-notes on this subject, based on personal 

 observation, are always most valuable. As regards 

 the birds of many parts of the world, such informa- 

 tion is still sadly deficient, although great advances 

 have recently been made in this direction. 



P. L. S. 



3 Hanover Square, London, W. 

 Sept, 1st, 1890. 



