1-14 On n new Marmoset from the Penivtan A7na:ons. 



more slender skull, and no naked gnlar patch in the female. 

 It is to be hoped that male cpecimoii.s will shortlv b<; obtained, 

 so that the pouch-structure in that sex can 1)0 ol)served. 



Major Stevejison Ihiinilton states that the specimen M'as 

 captured in tlie verandaii of his house. 



XVir. — A neio ^farmoset from the Peruvian Amazoris. 

 By Oldfield Thomas. 



(Published by permission of the Trustees of the British Museum.) 



Leoniocehua inounseyi, sp. n. 



Closely allied to L. a^nculatns, Thos.*, with which it agrees 

 in all essential characters, but distinguished by the following 

 ])oints : — Terminal ticking of nape-hairs commencing rather 

 further forward, on the hairs between the ears instead of 

 furtiier down the neck. Dorsal marbling rather more coarsely 

 conspicuous. Fur of under surface, including groins ami 

 inner sides of thighs, longer and denser, and the hairs all 

 with distinct blackish bases instead of being wholly reddish. 

 Upper side of hands and feet rather more prominently gi izzlcd 

 with fulvous. Tail, beyond its basal reddish-mixed inch, 

 abruptly deep black, without any trace of the more extensive 

 fulvous (rrizzlinj; for three or four inches which forms so 



... 



marked a cluiracteristic of L. ajn'citlntus. 



Dimensions of the type (measured in tlesh) : — 



Head and body 175 mm.; tail 3U0; hind foot 5^; 

 ear 24. 



Skull : gnatliion to occiput 4fi. 



Ilab. Kio I'acuya, opposite Sapote, Lower Ucayali. Alt. 

 250 feet. 



Ti/pe. Adult niide. Jl.^l. no. 20. 1. 9. 1. Original num- 

 ber 2. Collected 25th July, 1912, by Mr. J. J. Mounsey. 

 One specimen. 



Of the various characters above noted, the most njarked is 

 the difference in the extension of the grizzling of the base 

 of the tail — a character quite constant in otiier species and 

 one that seems certainly to justify the distinction of the 

 I'acaya marmoset. 



♦ Ann. & Mag. Nat. Hist. (7; xiv. p. 190 (1904) ; Elliot, Primates, i, 

 p. 204 (lUiyj. 



