270 Mr. O. Thomas on 



B. Molars |-. Iiicisoi-s |. Subgenus Vanipyt'odcs*. Type 



V. Caraccioh', Thos. 



C. Molars §. Incisors f. Subgenus Vamp>/nscus'^\ Type 



V. hidens, Dobs. 



D. Molars f . Subgenus Vanijujressa *. Type V. pusillus, 



Wagn. 



Rhipidomys Good,fellowi, sp. n. 



General external appearance almost precisely as in 7i. Couesi. 

 Fur unusually short, close and straight, only about 6 millim. 

 long on the back. Colour above of the same brownish-fawn 

 tone found in the browner examples of R. Couesi, perhaps 

 rather darker mesially. Sides clearer greyish fawn. Under 

 surface very short-haired, dull greyish with a buflfy tinge, 

 the bases of the hairs slaty, the tips dull bafFy ; line of demar- 

 cation on sides quite indistinct. Hind limbs and outer sides 

 of fore limbs like body; inner sides of fore limbs whitish, 

 whiter than the belly. Ankles and upperside of hind feet 

 brown, the hairs at bases of claws white. Tail with nearly an 

 inch of its base covered with the grey hairs of the body, the 

 remainder uniformly blackish, the terminal half more bushy 

 than in the allied species, the scales being practically hidden. 

 Mammae 1—2 = 6. 



Skull rather smaller and more delicate than tliat of 

 R. Couesi (comparing old specimens of eacli species), with a 

 lighter narrower muzzle ; nasals extending rather further back. 

 Interorbital region smooth, flat, sharp-edged, evenly broaden- 

 ing backwards. Palatal foramina rather smaller. End of 

 palate level with hinder edge of m.\ 



Dimensions of the type (measured in skin) : — 



Head and body 186 millim. ; tail 191 ; hind foot (wet) 29; 

 ear (wet) 14. 



Skull : extreme length 39 ; basilar length 31'6 ; greatest 

 breadth 20; nasals 14'6x4"6; interorbital breadth 6T ; 

 palate length from henselion 17; diastema 11; palatal 

 foramina 8T x o"o ; length of upper molar series 6. 



Hah. Upper Kio Napo, at mouth of llio Coca. 



Type. Female. Collected in June 1899, and presented to 

 the 13ritish Museum, by Walter Goodfellow, Esq., in whose 

 honour it is named. 



This Upper-Amazonian species is most nearly allied to the 



Trinidadian R. Coutsi, All., and the Peruvian h'. leucodactylus, 



Tsch., but may be distinguished from either by its much 



shorter fur, duller-coloured under surface, bushier tail, and 



* Nomiua nova. 



