Conepatus, Phyllotis, and Akodon. 469 



Probably most nearly allied to, and of about the same size 

 as, A. punctulatus, Thos.* Fur rather short, close and 

 almost crisp, the ordinary hairs about 8 miliim. in length, 

 though these are mixed on the back with much longer fine 

 hairs 12-13 miliim. long. General colour above dull yel- 

 lowish, rather, but not conspicuously, darker in the middle of 

 the back. Muzzle, cheeks, rings round eyes, and base of ears 

 clearer and deeper buffy yellow. Longer hairs of back brown, 

 tipped with white. Under surface dull whitish, fairly well 

 defined, the bases of the hairs plumbeous except on the chin, 

 where they are white to the roots. Ears rather short, well- 

 haired, of about the same colour as the head. Upper surface 

 of arms and legs, as far down as the metapodials, orange- 

 yellow ; fingers and toes white ; fifth hind toe (without claw) 

 barely reaching to the base of the fourth. Tail about as long 

 as the body without the head, well-haired, its upper surface 

 dull orange, its lower white. 



Skull very different from that of the more typical Akodons, 

 narrow, strongly bowed, its upper outline very convex and 

 its interorbital region sharply square-edged, though not 

 ridged. Nasals short and rather broad. Interparietal very 

 small. Palatal foramina long. Molars of normal Akodont 

 structure. 



Dimensions of the type (measured in the flesh) : — 



Head and body 100 miliim. ; tail 75 ; hind foot (s. u.) 19*5, 

 (c. u.) 21-5 ; ear 16. 



Skull (much damaged) : extreme length 26'5 ; nasals 

 8'5 X 3*7 ; interorbital breadth 4'9 ; breadth of brain-case 

 11*4; length of upper molar series 4*2. 



Hab. Calalla, Rio Colca, near Sumbay, Peru. Altitude 

 3500 metres. 



Type. Male. B.M. no. 0. 10. 1. 77. Original number 

 1109. Collected 19th June, 1900, by P. O. Simons. 



This is an isolated species, apparently only allied to A. punc- 

 tulatus, from which it is distinguishable by its very different 

 colour. 



Besides these three species, Mr. Simons's Caylloma and 

 Arequipa collection contains examples of the remarkable 

 Chinchilhrfa sahamce, of Akodon pulcherrimus, Phyllotis bol't- 

 viensis, and Reithrodon pictus. 



* Ann. & Mag. Nat. Hist. (6) xiv. p. 361 (1894). 



