On the Swaiuji-Hats of J-Jast Africa. 



irj 



Eefet'e7iees. 



V. I*. ('. IIoKK. *' PvcnogouiJu," St-ieDtllic llosulU of tli-j Voyage of 



H..M.S. 'CliiillVn-rLT,' 187.'5-7(5.— Zoolojry, v.)l. iii, 1881. 

 K, Miiitirs. " Dio I'liiitDpodun," Wisd. Kigobu. d. TiofMce Ex. ' VulJiviii,' 



IM. iii. pp. 178-1'JO. 

 T.' V. Ilonuso.v. " t)ii a now rvcnopoi)iil from theSoiilh Polar Itegioiis," 



.\iiii. & .Ma-,'. Nat. Uist. (7) vol. xiv. p. 4.">8. U»()4. 

 K. IJurviKu. Tycuogouides du Fraii^ais Exped. antarct. francaise.' 



liK)(!. 

 T. V. Iloi)U.soN. " Pvcno^roiiida," Voyage of the * Diacovery.' — Natural 



History, vol. iii. I'MT. 

 . " Pyonogonida of the Scoltisii National .Viitarctic E.xpedition," 



Tram. liov. Soo. Edin. vol. xlvi. pp. 150-188. l!J08. 

 J. C. C. LoMW. " Dio I'nntopodeii du ' Siboga ' Expoditioii," ' Siboga' 



ExiH'ditio, Monog. xl. l'J08. 

 E. BouviKii. " Pyciiogonidt's du ' Pouniiiui P.is,' " Ueuxii'ine Exped. 



autarct. fiau9aise. lUli*. 



IX. — On the Swamp- Rats (Otomys) of East Africa. 

 By Guy Dollman. 



(Piibli.-bed by pertuissiou of tbe Trustees of tbe Britisb Museum.) 



In the following ievi.sioM of the East-African swamp-rats it 

 lias been fouiiil necessary to modify considerably the arrange- 

 ment adoj)ted by Wroughton in his 1900 paper ''*■. Tiie 

 forms tropicuUs, nyikm, angoniensis, orestes, and dejitl are 

 here raised to full specitic rank, tropicalis taking the place of 

 irroratus, which species, on account of its cranial structure 

 anil lamina formula, is not considered a near enough relative 

 for the name to be used in connection with the Kast-AtVican 

 iorms; in this manner we confine i/vora/?^.s and its subspecies 

 to the country south of the Zambesi. As subspecies ot" 

 tropicalis we then have eif/onis and two new forms from the 

 Jombeni Hills and Mt. Nyiro. In this paper descriptions 

 are given of seven new Otomys, all from British East Africa 

 and Uganda. 



Key to the Species and Subspecies. 



A. Enwcr incisors with one deep groove. 

 W'Ulral surface of tail dark. 

 a. tn^ with 6 lamime. (^liuwcuzori East.) (1) dcuii, Tbo.s. 



.\nn. Jc Mng. Nat. Hist. (7) vol. xviii. p. 2(U (1900). 



