SOME MAMMALS IN THE SOUTHEUN SUDAN. 345 



those caught by the natives are usuaJly, they say, found in the 

 swamp. Of course, the dogs sometimes get a half-grown one in 

 the open, but the nativ^es say they never catch a full-grown one. 



The habits of these animals are almost exactly those of the 

 Zambesi Lech we, as is their general appearance, method of hold- 

 ing their heads when running, and the manner in which the heid 

 splashes through shallow water. When the plain is water-logged, 

 I have seen the whole herd standing in Avater halfway up to 

 their hocks, just as I have seen the Lechwe hei'ds in the Kwando 

 swa.mps of the South and elsewhere. 



The young ones seem rather delicate and difficult to rear in 

 captivity. 



I have never seen in this herd the old dark rams without the 

 white wither-patch spoken of by Col. Roosevelt. The younger 

 rams have an indistinct patch, but the older the animal the more 

 defined the patch, in my experience. There are aberrant types in 

 all species, or possibly in some localities there may be variety of 

 type, but I do not think anyone else has ever had so nnique 

 opportunities of studying a herd at close quarters as I have 

 had, and in a large one, such as this, there cannot fail to be 

 animals of all ages ; besides which I have been able to watch each 

 individual male separately, and am sure none of them display 

 this peculiarity. 



Cob (Kobus). 



Cob extend all the way along the west bank of the Bahr-el- 

 Gebel from south of Rejaf to beyond Shambe in suitable localities. 

 There is a very gradual but well-mai'ked variation in type from 

 t!ie quite brown-eared specimens seen near Rejaf through the 

 buff-eared tj'pes from between Monga.lla and Tombe to the 

 perfectly white-eared but rufous-bodied animals foiuid opposite 

 Bor. The latter agree with what is known as "Vaughan's Cob in 

 all characteristics ; but they shade off gradually southwards into 

 the typical Uganda Cob found on the same side of the river. On 

 the east baiik of the Nile " station " is much more irregular. 

 However, Uganda Cobs are found more or less sporadically from 

 Mongalla northwards, but, so far as I know, the intermediate type 

 is not found, and after a ga.p wherein no Cobs occur, the typical 

 Kohits leucoiis begins to occur in the plains near Jonglei. 



The " Vaughan '' Cobs opposite Bor were seen in open couiitry 

 near forest, where a herd of some sixty grazed with several parties 

 of Reedbuck and Thiang. They had the Cob-like habit of 

 mounting ant-heaps to scrutinize intruders. This herd had never 

 been molested, and I found it very tame and easy to approach so 

 long as concealment was not attempted. 



Probably the exti'cme permanent southern limit of the true 

 leucotis is at Jonglei on the east bank of the Bahr-el-Gebel, lat. 

 6° 45' I^T. ; here they are tolerably numerous over an aiea of about 

 20 square miles in a strip along the river. They spend the nights 

 and mornings during the dry season, as a rule, in the open plains, 



