the Species of the Genus Cuvia, 155 



Skull: greatest upper length 62 ; coiidylo-incisive length 

 58; zygomatic breadtii 35; nasals 19'7x8*5; interorbital 

 breadth 12*6 ; breadtii of parietals across brain-case 24'5 ; 

 diastema 17'4: ; bullaj 12-2x9'3; upper tooth-series l-i'G. 



Hah. Serra do Mar, Eastern Parana. Type from Roga 

 Nova. Alt. 1000 u). 



Type. Adult female. B.M. no. 3.7.1.96. Original 

 jiuniber 831. Collected 6th September, 1901, by Alphonse 

 Robert. Six specimens. 



This cavy of the Sena do Mar is readily distinguishable 

 from C. aperea bj- its dark colour, blackish back, buffy belly, 

 reduced chest-markings, and by the short and slender 

 nuizzh; of its skull. In the lowlands of the same region, at 

 Morretes (10 m.), M. Robert Ibund a representative of the 

 C. fa' g id a group. 



Next comes the well-known quiso of the Argentine and 

 Uruguay :— 



Cavia pamparum^ Thos. 



Cavia vvfescens ^jowj^arw???, Thos. Ann, & Mag. Nat. Hist. (7) viii. 

 p. 538 (1901). 



Allied to C. aperta^ but smaller; the skull usually about 

 62-63 mm. in length when adult. Colour as in aperea^ but 

 distinctly more greyish or olivaceous, less brown. Under 

 surface whitish or slightly drabby, the chest-patteru well 

 marked. 



Skull shaped as in aperea, but smaller ; the muzzle of the 

 sauie general proportion, not reduced as in C. rosida. 



Range from Corrientes and Uruguay southwards to 

 Southern Buenos Ayres. Specimens in Museum from " 20 

 miles north of Corrientes '' {Turner Hendtrson) ; Goya, 

 Corrientes {li. Perrens) -, Maldonado [Darioin) ; La Plata 

 [Thomas); Los Yngleses, Aj6, Buenos Ayres [E. Gibson); 

 and Bonifacio, S.W. Buenos Ayres (i?. Kenpj). 



All the specimens tiom the above considerable range agree 

 very closely with each other in size and colour, no geogra- 

 })hical variation being observable. Two of Mr. Gibson's Aj6 

 .sjjecimens, however, out of seven are abnormally larger than 

 tiie others, with decidedly larger skulls ; but these appear 

 more or less diseased, ami it is possible that they represent an 

 ■ infusion of domestic guinea-j)ig blood, although there is no 

 colour indication of this. Tlie other specimens of the same 

 lot are quite like the ordinary quiso. The size of the bulla 

 is a little variable, two of the Bonifacio series having this 

 12"1 and 11 mm. in length, that of the type being 11-7. 



