On new Argentine Species of Akodon., as 
XVII.—Two new Argentine Species of Akodon. 
By OupriecD THOMAS. 
(Published by permission of the Trustees of the British Museum. ) 
DuRineG the working out of Sr. Budin’s Patagonian collection 
the two following species of Akodon have? proved to need 
description :— 
Akodon neocenus, sp. n. 
A shaggy grey species allied to A. varius of Bolivia. 
Size and general appearance very much asin A. virdus, 
with the same loose and rather shaggy fur, which is, how- 
ever, rather longer and thicker; hairs of back about 13- 
14 mm. in length, intermixed with longer bristle-hairs 
attaining 17 mm. General colour greyer “than in varius, 
with less buffy, though the essential mixture of grey and 
buffy, varied by the dark tips to the hairs, is similar. Hands 
and feet whitish. Tail rather long, well haired, blackish 
above, whitish below. 
Elaleeuhe thes nacaie: mainawer and nore tapering poste- 
rioily than in A. varius. Supraorbital broad with Squared 
edges. Postero-external corners of brain-case developed into 
sharp angles, as viewed from above, this region being 
usually smoothly rounded ; but this may possibly hereafter 
prove to be merely individual, ‘Palatal foramina to the level 
of the front edge of the imiddle lamina of m'. Bulla: decidedly 
Jarger than in varius, their breadth in the type, taken at 
rivht angles to the diagonal length, 4°3 mm. 
“Incisors rather more proodont than in vardus, the angle 78° 
in two specimens as compared with 72°-75°. 
Dimensions of the type (measured on the spirit-speci- 
men) :— 
Head and body 108 mm.; tail 85; hind foot 23°5; ear 18, 
Skull: greatest length 29°2; condylo-incisive length 28:2 ; 
zygomatic breadth 14°8 ; nasals 11 x 3°2 ; interorbital breadth 
9°23 breadth of brain-case 13 ; palatilar length 12°8 ; palatal 
foramina 7; upper molar series (worn) 4°8. 
Hab, Neuquen, Rio Limay, Upper Rio Negro, Patagonia, 
Type. Old male in s spirit. Bae no. LA aroR oA Oo 
lected by E. Weiske, 4th November, 1910. 9 Presented 
by the Hon. N. Charles Rothschild, An imperfect skin, 
No. 11. 11.19. 10, also in collection. 
Ann. & Mag. N. ist. Ser. 9. Vol. iii. 15 
