Neotropical Mammals. 



167 



middle, the middle part projecting outwards on each side in 

 an angle at the premaxillo-maxillary suture. Posterior 

 narial opening narrow, the notch sharply V-shaped. Teeth 

 narrow throughout, the fifth maxillary tooth 6"2 x4-2 mm. 



Dimensions of the type (as taken by collector in the 

 flesh) :— 



Head and body 410 mm. ; tail 230. 



Cephalic shield 116x78. 



Skull : back of frontals to end of nasals 85 ; greatest 

 breadth 64 ; nasals, length 40, breadth, anteriorly 11, in 

 middle 19, posteriorly 12'5 ; ))alatal length 64 ; breadth of 

 palate between fifth maxillary teeth 13*3. 



J/ab. Tapia, Tucuman. Alt. 700 m. 



Ti/pe. Adult male. B.M. no. 3. 6. 6. 16. Original num- 

 ber 1910. Collected 23rd September, 1902, by L. Diuelli ; 

 presented by Oldfield Thomas. Two specimens examined. 



Marmosa chloe, sp. n. 



A small dark-coloured species, with creamy chest and 

 inguinal region. 



Size about as in M. fuscata^ Thos., and M. Klagesi^ All. 

 Fur soft and fine; hairs of back about 6 mm. in length. 

 General colour above sepia along the dorsal area, shading off 

 into bistre on the sides. Under surface, on throat, chest, and 

 inguinal region, pale pinkish or creamy buff, the hairs this 

 colour to tiieir bases ; but on the belly the slaty-based hairs 

 encroach on each side, so as to narrow the creamy part to a 

 mere median line. Sides of face with a large ill-defined 

 black patch surrounding the eyes, the paler area between 

 them less marked than in Klagesi. Lower cheeks cream-buff. 

 Ears naked, dark grey. Hands pale brown, feet whitish. 

 Tail with its short-haired part about half an inch in length, 

 the remainder naked, uniformly pale grey. 



Skull shaped very much as in J/. Klagesi', similarly 

 broad, with expanded zygomata and fairly well defined supra- 

 orbital ledges. Nasals expanded posteriorly. 



Dimensions of the type (measured in the flesli) : — 



Head and body 143 mm. ; tail 170 ; hind foot 21 ; ear 19. 



Skull: greatest length 33'7; basal length 30; greatest 

 breadth 18; nasals 14x4; interorbital breadth 5*2; breadth 

 of brain-case 13-5; palate, length 18'2, breadth outside 

 m^ 10*5 ; combined length of three anterior molariform 

 teeth 5-0. 



I lab. Dcmcrara River, 29 miles above Geon 

 Guiana. 



