280 Mr, O. Thomas on Mammals from 



and, tliirdly, the present form, wliich represents a considerable 

 extension eastwards of the range of tiiis type of agouti. 



As ah-eady stated, I feel quite confident that this animal is 

 not Wagler's D. exilis, as suggested by Allen, and therefore 

 now give it a new subspecific name. 



At Fiaulein Snethlage's suggestion I name this well- 

 marked form in honour of her helper and contributor Senhor 

 F. Lima, to wliom the Goeldi Museum is indebted for many 

 interesting mammals. 



52. Cyclopes didactylus, L. 

 ? . 152, 153. Villa Braga, R. Tapajoz. 



53. Marmosa domina, sp. n. 



(? . 160 ; ? . 156, 157, 159 (young). Villa Braga, R. 

 Tapojoz. 



M. ci/ierea group ; tail wholly brown. 



Fur not very long, hairs of back about 10 mm. in length. 

 General colour drabby grey, the sides becoming greyish 

 drab. Under surface not sharply defined, bufi'y, the chest 

 and inguinal region clear bufFy, the belly-hairs slaty at base 

 except along the middle line. Furry portion at base of tail 

 not very extended, only about an inch in length, and its hairs 

 not long, about 5-6 mm. Rest of tail naked, brown to the 

 tip, not whitened terminally, 



Skull, as usual in this group, with well-marked triangular 

 postorbital processes. 



Dimensions of the type : — 



Head and body 166 mm.; tail 250; hind foot 24'5 ; 

 ear 27. 



Skull : upper length 45 ; condylo-basal length 44'5 ; 

 zj'gomatic breadth 25; nasals 20x6; interorbital breadth 

 7*5 ; breadth across postorbital processes 8*4 ; palatal length 

 24'8 ; breadth across outer corners of m^ 13*8 ; maxillary 

 tooth-row 18*5 ; three anterior molariform teeth 7*2. 



I/ah. as above. 



Ti/pe. Adult female (basilar suture closed), B.M. no. 

 20. 7. 14. 39. Original number 156. Collected 19l.h June, 

 1917, by Friiulein Snethlage. 



Only two members of tliis group are without white on the 

 tail-tip — M. germana of Ecuador, which has a more or less 

 greyish-brown belly, and M. regina of Colombia, larger and 

 more buffy throughout. M. cinerea demerarce of Guiana has 



