INTRODUCTION. 



The first volume of this Catalogue contained the descriptions of 

 302 species and the enumeration of 3380 specimens. In this second 

 volume, which deals with the bulk of the Cyprinidae and the whole of 

 the Siluridse, the number of species and specimens amounts to 428 

 and 4434 respectively. 



The enormous increase in the number of species of Barbus, mostly 

 discovered during the last decade, shows how greatly an exploration of 

 the fresh-waters of Africa was needed. That our knowledge of these 

 fishes, from the purely systematic standpoint, is still far from complete 

 is shown by a large collection brought home from Angola by Dr. Ansorge 

 since the present volume was set up in type, as it contains examples of 

 as many as nine new species of Barhus to be added to the 185 here 

 defined. 



G. A. BOULENGER. 



Zoological Depabtaiexx, 

 19t7i November, 1910. 



