new Rodents from S. America. 255 



may be chosen as a " lectotype " to typify Waterliouse's 

 species. K. holiin'ensis was said to have come from tiie 

 " high tableland between Cochabamba and La Paz." 

 Specimens which T now refer to the same animal were 

 collected by J\[r. P. O. Simons at Paratani, close to Cocha- 

 bamba, and at other localities southwards to Sucre and Potosi. 

 Externally the species is greyish with a slight yellowish 

 suffusion, its belly being prominently whitish or creamy. 



Secondly, we have a form from Sajama, greyish above, 

 with scarcely any yellowish suffusion; the belly also grey, 

 not conspicuously ligiiter than the upper surface. In this 

 animal the bulla3 are slightly larger than in true holiviensis, 

 though the difference is not very great. 



The skull of this Cavy agrees nearly with that figured by 

 Meyen as ^' Galea musteloides " *, whose type locality is the 

 pass leading from Tacna to Lake Titicaca, and by no means 

 far from Sajama. The name Kerodon musteloides may 

 therefore be accepted for the Sajama species. 



Thirdly, on the shores of Lake Titicaca there is a species 

 which may be described as follows : — 



Kerodon auceps, sp. n. 



General colour more yellowish than in the other form«, 

 the upj)er surface mixed black and bufFy. Hairs of back 

 pale slaty, with a ^'cream-buff" subterminal ring and black 

 tip. Under surface pale buffy or creamy, lighter than in 

 musteloides, not so while as in holiviensis ; the bases of the 

 hairs pale slaty or " drab-grey.^' Ears longer than in the 

 other allied species. Orbital rings dull buffy, the black eye- 

 lashes very thick and strong. 



Skull broader and with more widely expanded zygomata 

 than in holiviensis and musteloides ; upper outline more 

 bowed; bullae much larger in every dimension. Meso- 

 pterygoid fossa fairly wide, its anterior border squarish or 

 broadly rounded. 



Dimensions of the type (measured in flesh) : — 



Head and body 225 mm ; hind foot 38 ; ear 25 f. 



(Skull: greatest length 54*5; condylo-incisive length 50 ; 

 zygomatic breadth 33'5 ; nasals 2U'6 X 8"3 ; inlerorbital 

 breadth 11*7; palatilar length 25; greatest horizontal 

 diameter of bullae 15*3 ; upper molar series (crowns) 15'2. 



Uab. Lake Titicaca. Type from Guarina (alt. 4000 m.), 



* Nova Acta Ac. Nat. Cur. xvi. pt. ii. p. 597, pi. xlii. figs. 4-7 (1833). 

 t 21-22 in specimens of boliviensis measured by the same collector. 



