454 Mr. O. Thomas on neio Mammals from 



Dimensions of the type (a female, measured in spirit) : — 



Head and body 96 raillim. ; tail 130 ; hind foot without 

 claws 24*5 ; ear 18. 



Skull : basal len,i;th 23-5 ; basilar length from henselion 22 ; 

 greatest breadth lo'S ; nasals, length 10 ; interorbital breadth 

 4-5; brain-case, length* 14*7, Ijreadth 12*7 ; diastema 6*7 ; 

 palatal foramina b'Q ; length of upper molar series 4-2. 



Hah. Paramo, south of Chimborazo. 



Type : B. M. no, 97. 1 1 . 7. 82. Collected by Mr. W. F. H. 

 Rosenberg. 



The external proportions and the narrowness and extreme 

 delicacy of the skull will readily separate T. paramorum from 

 any of its allies. 



Oryzomys vestitus, sp. n. 



Ver}' similar in proportions and general colour above to 

 0. mertdensis, but the fur very much longer, softer, and 

 woollier. Hairs of the back 14 or 15 millim. in length. 

 General colour grizzled fuscous grey, becoming more rutbus 

 posteriorly. Head clearer grey. Ears of medium size, very 

 thinly haired, the few short hairs pale brown. Under surface 

 of body uniformly dirty greyish, the hairs washed with dull 

 buffy terminally ; no white on chest or throat ; line of demar- 

 cation on sides quite indistinct. Hands and feet dull whitish 

 above. Tail comparatively well-haired, pale brown above and 

 below. 



Skull broad and peculiarly depressed in the cranial region, 

 the height of the brain-case being no greater than in an old 

 specimen of 0. meridensis^ while its breadth is very markedly 

 greater. Nasals short and narrow. Interorbital region flat- 

 tened above, its edges rounded or faintly squared, but not 

 ridged. Anterior edge of zygoma-root quite vertical, without 

 forward projection. Palatine foramina of medium length, but 

 narrow, and unusually far apart, the septum between them 

 1'5 millim. wide posteriorly; they end in front of m} a 

 distance equal to the length of m.^. Incisors broad and 

 strong, orange above, yellow below. Molars of normal 

 Oryzomys structure. 



l)imensions of the type (an adult male, measured in skin) : — 



Head and body 138 millim.; tail 166; hind foot 33"3; 

 ear 17. 



• The length of the brain-case may be conveniently taken in all 

 Murines from the hinder border of the interparietal to the centre of the 

 line dividing- the olfactory chamber from tlio rest of the brain-case. 

 Internally there is a transverse ridge ut this point, which readily shows 

 throuf!;h on the npper surface. 



