﻿NO. l6 NEW RODENTS FROM AFRICA — HELLER II 



Characters. — Closely allied to polionops; differs chiefly in pos- 

 session of white feet and underparts, the dorsal area lighter and 

 less russet, and the flanks salmon-gray; size greater, skull with 

 smaller molars ; compared to surdaster, the skull has smaller bullae, 

 and a longer rostrum. 



Coloration. — Dorsal coloration russet, the median region heavily 

 black lined ; rump lighter and more cinnamon in tone ; head tawny- 

 brown; sides of body and hind limbs salmon-gray, fore and hind 

 feet white; underparts white; the hair white to the roots, tail uni- 

 form broccoli-brown. 



Measurements. — Head and body, 120 mm.; tail, 160; hind foot, 

 23. Skull: greatest length, 31.2; condylo-incisive length, 28.3; 

 basilar length, 24.3; zygomatic breadth, 15; interorbital constric- 

 tion, 5; nasals, 11.5 x 3; post palatal length, 11.4; diastema, 8; 

 palatal foramina, 7 ; maxillary toothrow, 4.5 ; condylo-incisive length 

 of mandible, 19.3 ; coronoid-angular depth of mandible, 9.5. 



The type is the only specimen secured. An examination of the 

 members of the genus Thamnomys for generic characters shows 

 that only the type species venustus and rutilans possess the extra 

 internal cusps to the molars in a worn mature stage. It is only 

 possible in young unworn teeth of the dolichurus group to distin- 

 guish the ridge which marks this cusp. The long tufted tail, and 

 the tree dwelling habits are possessed by Epimys nigricauda and its 

 allies, and the external tail characters by the E. vereauxi group, but 

 the skulls of these species show no trace of the extra cusp. 



LEMNISCOMYS PULCHELLUS SPERMOPHILUS, new subspecies 



Uaragess Spotted Grass Rat 



Type from Mt. Gargues (Uaragess) Mathews Range, British 

 East Africa, altitude 7000 feet; adult female; number 181800, U. S. 

 Nat. Mus.; collected by Edmund Heller, August 26, 191 1; original 

 number, 4103. 



Characters. — Closely allied to massaicus, but dorsal coloration 

 lighter and without rusty suffusion ; foot smaller ; skull differs from 

 massaicus by greater concavity to the antorbital plate, and more 

 prominent hook at the angle ; teeth and bullae larger. 



Coloration. — Dorsal color dark olive, banded by ten light longi- 

 tudinal bands or series of spots of ochraceous, the median lines 

 enclosing a black stripe; head tawny-olive; ears olive, with long 

 rusty hairs about base ; sides lighter, the spots becoming wide 

 blotches of buff, and merging into the buffy wash of the underparts ; 



