404 



MR. OLDFIELD THOMAS ON MAMMALS 



known as M. ephippium, Jent., but rather larger, ranch longer and softer furred, and 

 more greyish smoky in colour. 



Fur long and soft, the wool-hairs about 15 and the longer hairs 18 millim. in length 

 on the back. General colour dark smoky grey, almost blackish along the middle of the 

 back, lightening to buffy or yellowish on the sides. Belly not sharply defined, the hairs 

 slaty at the base, yellowish white at the tip. Hands and feet silvery whitish above. 

 Tail nearly as long as the head and body, uniformly brownish, or slightly paler below. 



Dimensions of the type, an adult male, in skin : — 



Head and body (apparently much stretched) 155 millim.; tail 135; hind foot 

 (moistened) 2G'5. 



Skull, see below. 



This is evidently an insular highland form of the common little Rat spread over the 

 Malay Archipelago, to which I have generally applied the name of Mus ephippium, 

 but which will perhaps be found to grade into -the earlier described Mus concolor, Bly. 

 In any case, however, the highland form now described seems worthy of subspecific 

 distinction. 



"Common among the Igorrote sweet-potato fields on the top of Monte Data." — 

 J. W. 



Skull-dimensions {in millim.) of Species of Mus, Batomys, and Carpomys. 



Mus lu- 

 soniams. 



Basal length 



Basilar length : 



Greatest breadth 



Nasals, length 



„ breadth 



Interorbital breadth 



Interparietal, length 



„ breadth 



Anterior zygoma-root, length 



Palate, length from henselion 



Diastema 



Anterior palatine foramina, length 



„ „ combined breadth . 



Length of upper molar series 



Lower jaw, condyle to ineisor-tip 



,, bone only 



44 

 40-2 

 25-7 

 19-8 



5-9 



7 



5-3 

 11-6 



6-1 

 23 

 13-5 



3-2 



3 



9-3 

 33-2 

 31 



Mus inin- 

 dorensis. 



6- 



Mus 

 ephippium 

 neqrinus. 



' d- 



Batomys 

 granti. 



6- 



Carpomys 

 melanurus. 



Carpomys 

 phaurus. 



6- 



36 

 32-8 



(Lambda 

 to nasal 

 tip 30-3.) 



40-5 

 37 



39-3 

 36-3 



36 

 33 



19-5 



16 



22-2 



24-5 



23 



14-5 



13-1 



19-5 



16 



14-5 



4-7 



3-6 



5 



5-6 



4-6 



6-1 



5-2 



5-5 



5-2 



6-1 



5-6 



— 



5 



6-1 



4-8 



11 



— 



9-6 



11 



13 



3-8 



3-6 



4-5 



5-1 



3-8 



19 



16 



19 



19 



16-4 



11-2 



9-7 



12-8 



12 



11 



7 



6-5 



8-5 



7-8 



7-7 



2-6 



2-5 



3-1 



2-7 



2-8 



6-5 



5 



7-8 



8-8 



6-1 



26 



22 



30-2 



29-5 



26-6 



23-2 



19-7 



26-7 



27 



24 



