PREFACE. 



Although iu the Zoological " Catalogues " of the British Miiseani 

 the correct determination and exact description of the specimens are 

 the primary object aimed at, the systematic order in which the 

 species are enumerated has been a matter of due consideration with 

 the author of every volume. The Passerine Birds have received as 

 serious attention in this respect as any other group ; but it must be 

 confessed that the difficulties attending a satisfactory arrangement 

 have proved to be insurmountable. What one family may have gained 

 in more precise limitation, another has lost in the opposite direc- 

 tion ; and in no part is this more apparent than in that assemblage 

 of genera which is termed the family of Timelildce, and of which 

 Canon Tristram in a recent paper (' Ibis,' 1883, p. 38) speaks, not 

 without reason, as " the waste-paper basket of the puzzled syste- 

 matist."' The size to which the present volume has grown may 

 testify to the convenience of such a receptacle ; but, at the same 

 time, its need should incite ornithologists to renewed efforts to dis- 

 cover characters or combinations of characters on which an at least 

 practically useful arrangement of these birds could be based. Ex- 

 ternal characters have evidently failed to supply this base b\- them- 

 selves ; what aid can be obtained from an examination of the internal 

 organs remains to be seen. But it seems to me that investigations 

 in the latter direction must lead to more numerous subdivisions 

 than ornithologists are inclined to admit at present. 



ALBERT GiJNTHER, 



Keeper of the Department of ZooJogij. 



British Museum, 

 July 1, 1883. 



