4.4: Mr. 0. Thomas on 



V. — Small Mammals from South America. 

 By Oldp^ield Thomas. 



(Published b}' permission of the Trustees of the British Museum.) 



Leontoc^hus mi'das egens, subsp. n. 



General characters of true Guianan midas, bui back more 

 strongly suffused with dark buffy, generally througiiout, and 

 in all cases across tlie shoulders. Black o£ the head less 

 deep and less continued down on to the back, tiie grizzled 

 buflfy of the back going further forward on the nape. Hands, 

 instead of being wholly " ochraceous " or " ochraceous buff," 

 only of this colour on the outer half of the wrist, the meta- 

 carpus and digits being decidedly lighter coloured, " buff " 

 or " cream-buff." Feet also rather lighter than in midas, 

 though the difference is less conspicuous. 



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



Head and body 229 mm. ; tail 384 ; bind foot 65 ; ear 40. 



Skull : greatest length 49' 5. 



Uab. Obidos, Lower Amazons. 



Tt/pe. Adult female. B.M. no. 12. 5. 11. 5. Original 

 number 58. Collected 15th February, 1912, by Fraulein 

 Dr. E. Snetlilage ; presented by the Goeldi Museum, Para. 

 Five specimens examined. 



This Amazonian form of the common yellow-handed 

 marmoset is closely similar to the typical Guianan animal, 

 but may be distinguished by the paler colour of its hands, a 

 difference verified on five examples of egensas compared with 

 ten of midas. Curiously enough, two specimens from the 

 Moon Mountains, the nearest locality in Guiana to Obidos, 

 have hands of an even darker tone than those of British 

 Guiana, and resemble in this respect one from Cayenne which 

 1 have always considered to represent Geoffroy^s rujimanus. 



Fells pardinoides emerifa, subsp. n. 



General characters of F. pardinoides, including size, tlie 

 backward direction of the nape-hairs, and the general colora- 

 tion. But the feet, both fore and hind, instead of being- 

 blackened below, as is usual in the majority of cats, are not 

 or scarcely darker below than above, where they are of a 

 uniform " clay-colour " ; the heel alone is blackisii, as in the 

 allied forms. White ear-patches larger than in pardinoides 



