new Rodents from S. Amnu'ca. 255 



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

 species. K. holiviensis was saitl to have come from the 

 " high tableland between Cocliabamba and La Paz." 

 Specimens which T now refer to the same animal were 

 Collected by Mr. P. O. Simons at Paratani, close to Coclia- 

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

 Externally the species is gre^'ish with a slight yellowish 

 snft'usion, its belly being prominently whitish or creamy. 



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

 with scarcely any yellowish suffusion ; the b^lly also grev, 

 not conspicuously lighter than the upper surface. In this 

 animal the bulla? are slightly larger than in true holiviensiy, 

 though the ditforence 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 

 tar from Sajama. The name Kerodon musteloides may 

 theretbre be accepted for the Sajama sjiecies. 



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 ui)per 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 ; tiie 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; bulla; 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 b-i'b ; condylo-incisive length 50; 

 zygomatic breadth 33*5; nasals 20"6 x 8"3 ; interorbital 

 breadth 11-7 ; palatilar length 25; greatest horizontal 

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



Hah. Lake Titicaca. Type from Guarina (alt. -iOOO m.), 



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

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



