new Xeotroplcal Mammah. 219 



Proechimys* rosa, sp. n. 



Size about as in P. chrysceolus, Thos. Back coarsely 

 spinous, sides rathei* less so, runijj and outer sides of limbs 

 without spines ] spines of back about 20 millim. long (without 

 terminal bristles) by 1*2 millim. wide. General colour rather 

 similar to that of P. chrysceolus and equally heavily black- 

 lined, but more fulvous and less rufous, the hairs of the back 

 with deep fulvous subterminal and black terminal bands. 

 Forehead, cheeks, and sides of neck greyer. Rump and hips 

 brownish fulvous. Under surface pure white. Outer sides 

 of arms and legs brownish, inner sides white ; upper surface 

 of hands and feet pale brownish, becoming white at the bases 

 of the toes. Tail fairly well haired, black above, dull whitish 

 below. 



Skull large and heavily built ; nasals very long, reaching 

 back past the front edge of the orbit, narrow, evenly tapering 

 backwards; supraorbital edges broadly ridged, the ridges 

 evenly continuous posteriorly with those that run forwards 

 from the outer corners of the interparietal ; molars narrow 

 vertically ; hamular processes of pterygoids broad and spatu- 

 late ; bulla? rather small. 



Dimensions of the type (measured in the flesh by col- 

 lector) : — 



Head and body 235 millim. ; tail 168 ; hind foot (s. u.) 6'2 ; 

 ear 27. 



Skull: greatest length 60; basilar length 43*5; greatest 

 breadth 28"2 ; nasals 22*6 x7'l; interorbital breadth 12'6; 

 greatest breadth across temporal ridges 22"3 ; height of molar 

 in centre 3*3; palate length 21 ; diastema 13'3 ; palatal 

 foramina 5 x 3*3 ; breadth of hamular processes 2*4 ; breadth 

 between bullee on basilar suture 3*6 ; length of upper molar 

 series 9*5. 



Bah. Santa Eosa, S.W. Ecuador. Alt. 10 m. 



Type. Male. B.M. no. 0. 1. 1. 40. Original number 434. 

 Collected 29th June, 1899, by Mr. Perry O. Simons. Three 

 specimens. 



Mr. Simons obtained six specimens of Proechimys at Santa 

 Kosa, and these prove to belong to two species — one paler, 

 with white feet, broader nasals, and broader malars, which 

 appears to belong to the group containing P. semispinosus, 

 Tomes, and P. decunianus, Thos., to the former of which I 

 provisionally refer it ; and the second, now described, darker 

 coloured and with brownish feet, evidently most nearly allied 

 to P. chrysceolus. From that animal, whose habitat is 



* Eihimys, auctorum, !See Allen, Bull. Am. Mus. xii. p. 257 (1899). 



