from the Neotropical Region. 303 



Dimensions of the type (an adult male skin) : — 



Forearm 40 millim. ( = 1*56 inch). 



Head and body (measured by collector in flesh) 50 millim. ; 

 ear (dried) 17 ; thumb, with claw, 9*2 ; middle finger — meta- 

 carpus 36, first phalanx 13"5, second phalanx 20, third 

 phalanx 10"5 ; tibia 15 ; hind foot, with claws, 10"6 ; 

 calcar 7*2. 



Skull: greatest length 19"6 ; basal length 16; greatest 

 breadth 9"6 ; breadth of muzzle at inflations, just over ante- 

 orbital foramina, 5*7 ; interorbital breadth 4*6 ; front of upper 

 canine to back of ^^ 8. 



Ilab. Imravalles, Costa Rica. 



Coll. C. F. Underwood, Nov. 8, 1895. 



Rhipidomys venezuelce, sp. n. 



Closely allied to Rh. macrurus, Gerv., with which it shares 

 the general rich rufous colour, long tail, and sharply defined 

 pure white belly. Ears large, much larger and, especially, 

 broader than in Rh. macrurus. General colour above rather 

 orange-rufous in the type (an old male), but in a younger 

 female clearer rufous, similar to some specimens of Rh. Sumi- 

 chrasti. Hands and feet, as usual, with the metapodials 

 brown mesially, the remainder and the digits white. Tail 

 long, uniformly dark brown above and below, hairy and 

 tufted, but less so than in most of the larger species of the 

 group. 



Skull with fairly long nasals ; a rather narrow interorbital 

 region, whose edges are sharply ridged. Interparietal large, 

 its anterior edge very concave forwards. Anterior palatine 

 foramina extending backwards to the level of the front edge 

 ofHLi. 



Dimensions of the type (an adult male, measured in the 

 flesh by collector) : — 



Head and body 155 millim.; tail 160; ear 20. In the 

 dried state the hind feet are 28 millim. long and the ear has 

 shrunk to 19 millim. 



Skull : basal length 31'2 ; basilar length from henselion 29; 

 greatest breadth 19*5 ; nasals 12 X 4 ; interorbital breadth 5*2, 

 interparietal 5*1 X 9*2; palate length from henselion 15'1 ; 

 diastema 10; anterior palatine foramina 7*6 x3j length of 

 upper molar series 5*1. 



Hah. Merida, Venezuela, alt. 1630 metres. 



Coll. S. Briceno, March 5, 1896. 



Besides the differences in the size of the ears and the 

 hairiness of the tail this species differs from Rh. macrurus by 



