4 o2 ZOO-GEOGRAPHICAL NOTES. 



look for true steppe birds in the eastern division of our country, 

 although we shall also meet with forms which have hitherto 

 been known as belonging exclusively to the east. Among the 

 former, the ostrich ought to rank first ; it is always found 

 wandering about in flocks, of often thirty birds ; it keeps 

 strictly to the steppe, especially where covered with brushwood, 

 and avoids altogether forest, mountain lands, and damp tracts. 

 From the class of birds of prey it may suffice to select Melierax 

 polyzonus, Riipp. ; Helotarsus ecaudatus, Daud. ; and Poliornis 

 rufipennis, Strickl., the last of which has its proper home here. 

 I am astonished at never having yet met with the bird of 

 the steppe par excellence, Gypogeranus serpentarms, L., though I 

 have no doubt of its existence here. As a matter of course, 

 all the birds dwelling in the steppe region farther to the north 

 frequent also our southern steppes, and therefore no special 

 enumeration of them is necessary, for they consist for the most 

 part of forms widely distributed over Africa. Turning to the 

 purely eastern varieties, we first of all come across SchizorJiis 

 leucogastra, Riipp., which even in Latiika replaces Schizorhis 

 zonura, Rlipp. (a native of all other parts), and is the prevailing 

 form far down to the south (Uganda). Its western limit 

 may be laid down at 3 2° 30' E. long. The following are also 

 purely eastern birds : — Dryoscopus nigerrimus, Reich. ; Sper- 

 mestes caniceps, Reich. ; Crithagra cJiloropsis, Cab. ; Caprimulgus 

 inomahts, Heugl., all of which are caught in Latiika. It 

 must further be remarked that none of these eastern species 

 cross to the western side of the Bahr-el- Jebel valley ; on the 

 contrary, several do not even reach it, but confine themselves 

 to the eastern slope of the mountains of Obbo. 



The circumstances connected with the flora and fauna of 

 the western side of the river do not assume such a simple 

 form. As already stated, there is here also a chain of moun- 

 tains running from the lake towards the north, at a greater or 

 less distance from the river. At about 4 8' N. lat. this range 

 leaves the river, and, gradually decreasing in height, runs in a 

 north-westerly direction to the Bahr-el-Ghazal ; all the country 

 lying to the north and east of this chain, consequently the whole 

 triangle formed by it, the Bahr-el-Ghazal, and the Bahr-el- Jebel, 

 belongs to the steppe domain, and the fauna assumes a corre- 



