184 MR. O. THOMAS ON SMALL [Mar. 3, 



beyond that already recorded in the two papers on Emin's Mam- 

 malia ^ 



7. SciuRus ANNTJLATUs, Desm. 

 a, h. Two specimens. 



8. SciURUs CEPAPi, Smith. 

 «, 6. c? • Kikuyu. 



c. 5 . Kikuyu. 



d. $. 



9. Xerus erythropus, Geoffr. 

 a. One specimen. 



10. Otomys irroratus, Bts. 

 a~e, Mianzini. 8/89. 



These five skins exemplify very well the considerable variation 

 in colour to which this species is subject, two of them being dark 

 umber-brown, two dark sandy fawn, and the fifth grey, with a 

 wash of brown on the head and centre of back. These differences, 

 however, may be due merely to age, as, judging by the skulls, the 

 last described specimen is the youngest, and the first two the next 

 in age of the set, the fawn-coloured specimens being therefore the 

 oldest of all. 



All the five have 7 laminae in m^^ and 4 in mT", and therefore con- 

 firm on the whole the conclusions come to by Prof. Barboza du 

 Bocage ^ as to the identity of his 0. anchietce, which has 7-5 

 lamiuse in the two teeth, with 0. irroratus of S. Africa, which 

 ordinarily has only 6-4. There may be perhaps a tendency to an 

 increase northwards in the number of laminse in the last upper molar, 

 as S.-African specimens seem very rarely to attain the number found 

 in all of the Mianzini ones, which are the most northern recorded. 



11. Otomys jacksoni, sp. n. (Plate XV.) 



a. Crater of Mt. Elgon, at 13,200 ft. 17/2/90. Type \ 



h, c (without skulls). Ditto. 



Allied to O. irroratus, but readily distinguishable by the lower 

 incisors having two deep grooves on their anterior faces instead of 

 only one. 



Size rather smaller than in 0. irroratus ; general form, as usual, 

 very vole-like. Fur excessively long and soft, the general mass of 

 the hairs on the back attaining a length of 18-20 millim. 



' P. Z. S. 1888, p. 8, and 1890, p. 447. In the second of these two papers a 

 misprint occurs (p. 446), which I may take this opportunity of correcting. 

 The type specimen of Anomalurus orientcdis, Peters, is there said to be in the 

 British Museum, but it should, of course, have been Berlin Museum. 



■^ J. Sci. Lisb. (2) iii. p. 206 (1889). 



" The single skull, on which of course the species is really founded, was not 

 defuiitely allocated to any one of the three skins ; but in its size it appears to 

 fit a the best, and as it certainly belongs to one or other of the three, the point 

 js not of very great consequence. 



