516 Mr. 0. Thomas o?i 



zygomatic breadth 22-6 ; nasals 19"5 x 5*6 ; interorbltal 

 breadth T'l ; palatal length 23"3; three anterior molariform 

 teeth 6-7. 



An older skull of similar length attains 25 mm. in zygo- 

 matic spread. 



Hah. Trinidad. Type from Caparo. 



Type. Adult male. B.M. no. 97. 6. 7. 24. Collected 18th 

 January, 1897, by Dr. Percy Kendall. 



The Trinidad Marmosa is a larger, stronger-coloured 

 animal than its neighbours on Grreuada and Tobago and than 

 that on the opposite mainland which I assign to M. mitis, 

 Bangs. The true M. murina of Guiana has much smaller 

 teeth. M. vnlis extends along the mountainous ranges from 

 Santa Marta through Merida to Cumana, and appears to 

 extend southwards into Colombia and Ecuador. Tiie hairs 

 of the sides of its belly are always conspicuously slaty at 

 base, in contradistinction to the following form. 



Marmosa mitis casta, subsp. n. 



Size and other characters as in M. mitis, but nearly or 

 quite the M'hole of the hairs of the under surlace cream- 

 coloured to their bases. If a i^w of the hairs on each side of 

 the belly have slat}^ bases, these are quite hidden by the 

 long cream-coloured ends, while in true mitis the area of 

 slaty-based hairs is readily perceptible. 



Skull as in mitis. 



Dimensions of the type (measured in flesh) : — 



Head and body 138 ram. ; tail 190 ; hind foot 22 ; ear 27. 



Skull : condylo-basal length 37*2 ; zygomatic breadth 20'5; 

 three anterior molariform teeth 6"4. 



Bab. San Esteban, Carabobo, N. Venezuela. 



Type. Adult male. Original number 207. Collected 6th 

 February, 1911, by Mr. S. JVJ. Klages. Twelve specimens 

 examined. 



Marmosa dorothea, sp. n. 



General appearance about as in M. mitis casta ; skull- 

 ridges as in M. impavida. 



Colour above a rather pale '^ murina ''''-coXonv, paler than 

 " cinnamon '^ and rather more suffused with "russet." 

 Under surface wholly " cream-buff/' the hairs light to their 

 roots ; line of demarcation on sides well marked. Hands and 

 feet whitish. Tail grey, the end gradually becoming white 

 or whitish. 



