NO. lO RODENTS FROM BRITISH EAST AFRICA HOLLISTER 3 



PEDETES SURDASTER CURRAX, subsp. nov. 

 Type from Kabalolot Hill, Sotik, British East Africa; adult male, 

 skin and skull, U. S. Nat. Museum No. 181762. Collected May 7, 

 1911, by Edmund Heller. Orig. No. 1802. 



Diagnosis. — Decidedly more yellowish, less reddish, than Pedetes 

 surdaster siirdaster, and with longer tail. Skull with upper outline in 

 profile as in surdaster, but with the high rostrum and antorbital 

 region in general more like P. s. larvalis. Mastoids more enlarged 

 than in either, the skull with greater mastoid breadth. 



Measurements of type. — Head and body, 400 mm. ; tail vertebrae, 

 480; hind foot, 157; ear, y^. Skull: Condylobasal length, 75.3; 

 zygomatic breadth, 55.7; greatest breadth nasals, 19.0; height of 

 skull in front of orbits, from anterior alveolar border to highest 

 point on crown directly above lachrymal bone, 33.6 ; mastoid breadth, 

 46.1 [in numerous skulls of true surdaster from 41.9 to 43.8] ; upper 

 tooth row, crowns, 15.9. 



Remarks. — This new form is based on a single specimen which 

 cannot be matched for color or great mastoid breadth of skull by any 

 specimen out of a series of nearly fifty specimens from the type 

 locality of surdaster. All three forms of surdaster, from the Sotik, 

 Naivasha Plains, and Athi Plains, differ from the South African 

 P. cafcr in the shallowness of the anterior palatine depression. 



