NATURAL HISTORY 315 



beauty of plumage, hold their own against any bird of the 

 bush country. 



I could wish that this account, in which I have endea- 

 voured to give the general reader some idea of the natural 

 history of the countries through which the Expedition passed, 

 was more complete ; but the subject is too vast to deal with 

 adequately in so short a space. 



In conclusion I give Mr. Boulenger's interesting notes on 

 the fish of Lake Chad, which were collected "by Grosling: — 



" Until this collection reached the British Museum nothing 

 at aU was known of the fishes of the Chad basin. The very 

 remarkable agreement which was known to exist between 

 the fish-faunas of the Nile and the Niger and Senegal — so 

 many species occurring simultaneously in these rivers — 

 pointed to the fact that their separation must be very recent 

 from a geological point of view, and that a communication 

 by a great central lake or a series of lakes, of which the Chad 

 is a remnant, must have existed at no remote period. 



" This view has been amply confirmed by my examination 

 of the Chad fish as they were found to belong, with one or 

 two exceptions, to species common to the Nile or Niger, thus 

 realising in a most striking manner my anticipations, as 

 expressed by me when dealing with the very difficult fish- 

 fauna of the Congo. 



" Among the most striking forms found in the Chad and the 

 Shari are several representatives of the Mormyrs, curious 

 fishes confined to tropical Africa and the Nile, all of which are 

 possessed of weak electric powers, the electric apparatus 

 being situated on each side of the tail. These fish are well 

 known to Egyptologists, the long-snouted Oxyrhynchus and 



