38 BINAE LONNBBRG, MAMMALS COLLECTED BY THE SWEDISH ZOOLOGICAL EXPEDITION ETC. 



Naivasha, British East Africa, under the name of Lasiopyga pygerythra callida. As 

 this race is said to have »less yellow in coloration of back* it can hardly need 

 further comparison with the present specimens. The feet are said to be black even 

 in the young specimens. 



This monkey is the »Tumbi]i» of British East Africa. In its habits it is entire- 

 ly different from the Kima. The Tumbili does not live in thick forest but belongs 

 to more open ground. It is seen in the thornbush as well as on the acacia steppe 

 and runs much on the ground, sometimes rather far from any trees. The thin forest 

 belts which often fringes the East African rivers appears to be the regular home of 

 the Tumbili and to them they return and take refuge in the highest trees if any 

 danger threatens them. 



Sometimes they appear to have certain routes which they know of and use 

 when they seek safety. At Guaso Nyiri below Chanler Falls I had once seen a band 

 of Tumbilis run down from the thornbush to the trees at the river side, but when 

 I came there they had disappeared. A few days later I observed them almost in 

 the same place again, and I ran as quickly as possible with my gunbearers to inter- 

 cept them. It appeared almost certain that we should succeed because there were 

 only a few trees on our side of the river. When we came nearer, however, I saw 

 the last of the Tumbilis take a flying leap from a tree on a small island to the 

 opposite side, and thence they continued to travel with great speed along the river 

 on the opposite side. An examination of the conditions revealed how the Tumbilis 

 had reached safety. A tree had fallen from the north bank and lay across a branch 

 of the river forming a bridge to the western end of a small narrow island. At the 

 eastern end of the same a big tree leaned over towards the southern side so that 

 from its crown the monkeys could make a long leap and get hold of the branches 

 of a tree on the southern side. This accounted for the mysterious disappearance 

 the first time, and explained also why the Tumbilis ran down to the river at the 

 same place the second time. This was evidently a, to them, well known route which 

 they had used before. Only a young female which remained on the island, possibly 

 not daring to make the last long leap across the southern branch of the river, could 

 be added to the collections. The Tumbilis occurred usually in small flocks but 

 several times single Tumbilis were seen in the interior of the thornbush, sometimes 

 far from any other water than that in the holes dug by the Rendiles, as at Njoro 

 and Thera, in otherwise dry riverbeds. 



^ HoLLisTiER has recently (Smithson. Misc. coll. Vol. 56 N:o 2. Washington 1910, p. 11) described a 

 monkey of the patas-growp from Brit. E. Africa under the name of Erythrocebus wJiitei. The type locality of 

 this species is »Nzoia River, Guas Ngishu Plateaus. Matschie described 1905 a monkey from Ikoma and 

 belonging to this group under the name of E. baumstarlci. Although I have not myself seen any red monkey 

 during my expedition to Brit. E. Africa I think it worth mentioning that I heard stated by Dr. Walsh that he 

 had shot a red monkey which according to the description must have been a member of the paias-group. This 

 happened not far from Ulu station of the Uganda railroad in April 1911. Dr. W. observed it running at a 

 long distance and shot at it believing it to be a Cheetah, and he confessed to be very astonished to see this 

 strange-looking animal when he had killed it. The occurrence of a monkey of this group as far south-east as 

 Ulu appears rather interesting, but as I have not seei^ the specimen I cannot tell whether it belongs to any of 

 the species mentioned above, 



