the Genus Otomys. 273 



The colouring is much as in irroratus, but the pale Ijiitt" 

 speckling is in such ((uantity as to overpower the dark 

 ground and to give the effect of a dull golden colour. 



The normal dimensions are as follows : — 



Head and body 170 mm. ; tail 85 ; hind foot 30 ; car 20. 



Skull : greatest length 41 ; basilar length 35 ; zygomatic 

 breadth 20 ; length of upper molar series 9 ; bullte 7'5. 



The following are some actual measurements (in mm.) : — 



4.3.1.33. 4.3.1. .30. 4.3.1.31. 



Old cT. Ad. cT. Yg. d. 



Head and body 170 158 137 



Tail 85 75 74 



Hiud foot 30 27 27 



Ear 22 19 18 



Skull : 



Greatest length 42 41 38 



Basilar length 35 ? 31 



Zygomatic breadth . 21 20 19 



Upper molar series. . 9-3 9*3 9 



Bulkie 7'5 ? 7'5 



It is iuteresting to note that while the O.R.C. specimens 

 have all, without exception, six laminae in m^, two out of 

 three of the ]\lazoe specimens, which come from what I 

 regard as the northern limit of this form of tooth, have 

 seven laminae in m^. 



(9) Otomijs irroratus cupreus, subsp. n. 



6.4.3.43-48, 148-9. Zoutpansbcrg, Transvaal. (Rudd 

 Exploration.) Alt. 4500-5000'. 



More resembling irroratus in the proportionally longer 

 tail, but shorter in the hind foot and smaller in the skull 

 than either auratus or typical irroratus. 



The colouring is like that of the northern form^, i. e. the 

 place of the pale buff of auratus is taken by deep brown, 

 giving a generally coppery look to the specimens. 



The normal dimensions are : — 



Head and body 170 mm. ; tail 100 ; hind foot 28 ; ear 20. 



Skull : greatest length 39 ; basilar length 32 ; zygomatic 

 breadth 20 ; length of upper molar series 9 ; bullae 7. 



Some actual measurements are (in ram.) : — 



