Mammals from North Argentina. 133 



Skull : greatest median length 48 ; condylo-incisive length 

 44*7 ; zygomatic breadth 23 3 ; bimeatal breadth 25*5 ; 

 nasals 19*5 x 6'3 ; interorbital breadth 8*5 ; least breadth 

 across brain-case 20'3 ; palatilar length 21*5 ; palatal fora- 

 mina 11 ; bullae, diagonal horizontal length 16'8, height to 

 protruding part on top of skull 17 ; upper cheek-tooth series, 

 crowns 9, alveoli 9*7. 

 Hab, and type as above. 



So different does this " Raton Chinchilla," as Sr. Budin 

 calls it, look from anything known, that it was at first sup- 

 posed to represent a new genus ; but close study shows that 

 its peculiarities are only a further specialization of those 

 shown by Wolffsohn's Abrocoma murrayi, and that there is 

 no reason to separate it generically. It is, however, in any 

 case a very striking addition to the mammal fauna of Argen- 

 tina, the other species of the genus being Chilian or Peruvian. 

 The single specimen was trapped by Sr. Budin — to his 

 great delight — among the rocks on the Volcano of Casabindo, 

 at the very considerable altitude recorded above. Of H. ben- 

 nettii we have examples taken by Mr. Wolffsohn at 200 and 

 800 metres, and of H. murrayi at 600 metres in the lower 

 highlands of Chili. But how far they range up on the main 

 Cordillera I do not know. 



9. Lagidium vulcani, sp. n. 



S . 507 ; ? . 508. Casabindo, 4000 m. 



cJ. 538, 539, and a separate skull. Cerro Casabindo, 

 4800 m. 



" Shot among the rocks."— E. B. 



Near L. tucumanum, but much more suffused with buffy, 

 and with white incisors. 



General colour of adult strongly suffused with buffy, the 

 ends of the hairs more or less buffy yellow. Sides and belly 

 brighter yellowish. White axillary and inguinal patches 

 present. Face more greyish or whitish buffy than the body, 

 the colour there much lighter than in other species. Hands 

 and feet buffy whitish. Tail with the usual blackish under 

 surface. 



Skull larger than in tucumanum. Nasals fairly narrow, 

 slightly inflated anteriorly, but not broader than the pre- 

 maxillse. Frontal processes of premaxillse more surpassing 

 the nasals. Lacrymal bones larger, projected over the orbit. 

 Projecting area of bullce on top of skull of the same shape as 

 in tucumanum, but larger. Incisive fissure quite narrow, not 



