1902.] NEW BOLIVIAN RODENTS. 117 



outside and in, their edges whitish. Upper surface of hands and 

 feet well-haired, the haii- of the ends of the digits surpassing the 

 claws, silvery white ; fifth hind toe, without claw, reaching to 

 the middle of the second phalanx of the fourth ; palms and soles 

 naked, the pads large, rounded and j)rominent. 



Skvill with large nasals, very broad anteriorly. Interorbital 

 I'egion narrow, parallel-sided, concave in the middle line, the 

 concavity bordered by low rounded and inconspicuous ridges, 

 which do not overhang the orbit or run back on to the parietals. 

 Interparietal large and broad. Anterior plate of zygoma-root 

 concave anteriorly, with an overhanging point above. Palatal 

 foramina very long and open, broadest mesially, running to a 

 sharp point iDehind, where they reach to the level of the first 

 lamina of 7>i\ their edges very sharp and clearly defined. Posterior 

 nares level with the back of m'\ comparatively broad. Bvillje 

 small. 



Dimensions of the type, measured in the flesh by Mr. Simons : — 



Head and body 160 mm. ; tail 145 ; hind foot, s. u. 29, c. u. 30 ; 

 ear 25. 



Skull — greatest length 37; basilar length 31 ; nasals 15*2 x 6*1 ; 

 interorbital breadth (on the convex surface low down) 4, between 

 the ru.dimentary ridges 2*1; breadth of brain-case 14; inter- 

 parietal 4"3 X 10 ; zygoma-i-oot 3 ; palate leng-th 18 ; diastema lO'l ; 

 palatal foramina 9' 6 X 3' 2 ; length of upper molar series 7 ; 

 combined breadth of upper incisors 3. 



Sab. El Cabrado, between Potosi and Sucre, Bolivia. Altitude 

 3700 metres. 



Tijpe. Old female. B. M. No. 2.2.2.15. Original number 1568. 

 Collected September 20th, 1901, by P. 0. Simons. Two specimens, 



A young specimen, apparently of the same species, had been 

 previously obtained by Mr. Simons at La Paz, altitude 4000 m. 



Mr. Simons says of this animal : " Caught in thicket of oak- 

 like bushes ; nocturnal." 



Owing to its extreme general resemblance to Phyllotis, the 

 young specimen from La Paz had been supposed to be an example 

 of that genus with a wi'ongly numbered skull, bvit the later 

 examples prove that Mr. Simons was in this instance, as usual, 

 entirely correct in his labelling. 



EXPLANATION OF THE PLATES. 



Plate VIII. 

 Neoctodon simonsi, p. 115. 



PtATE IX. 



Pigs. 1, 2, 3. Andinomys edax (p. 116), skull. 



Fig. 4. Andinomys edax, right upper tooth-row : a, adult ; h, young. 



5. Chinchillula saliamce (p. 116), right upper tooth-row : «& 6 as before. 



6. Andinomys, right lower tooth-row : a & S as before. 



7. Chinchillula, right lower tooth-row : a & & as before. 

 Figs. 8, 9, 10. Neoctodon simonsi (p. 115), skull. 



Figs. 11, 12. Neoctodon, right upper and right lower tooth-rows. 



