5G8 Mr. 0. Thomas on new 



near ochraceous tawny of Ridgway, instead of cream -buff. 

 Posterior back finely ticked with buffy, the hairs commonly 

 black with buffy (ochraceous-buffy) tips, while in palliata 

 there is a variable mixture of completely black or buffy 

 (cream-buff) hairs. Tail with many of its hairs buffy, espe- 

 cially towards its tip. 



Skull in general like that of palliata, but on the average 

 the mesopteiygoid fossa is more squarely open anteriorly and 

 the zygomata are less broadened vertically, especially in their 

 anterior part. Thus in male and female quichua the vertical 

 height anteriorly is 11 mm. and 10 mm., while in palliata it 

 is 14 mm. and 12 mm. respectively, the general size of the 

 skulls being about the same. 



Dimensions of male and female specimens, measured in the 

 flesh, the female the type : — 



Head and body 530 and 485 mm. ; tail 595 and 582 ; hind 

 foot 145 and 130. 



Skulls : greatest length 113, 104 ; condylo-basal length 

 102, 90"5; zygomatic breadth 81, 73 ; combined length of 

 premolars and molars 36, 34"5. 



Hob. N. W. Ecuador. Type from the Rio Blanco, 20 miles 

 W. of Mindo (about 79° 10' W., on Equator). Alt. 2500'. 

 Other specimens from Mindo, 4200'. 



Type. Adult female. B.M. no. 13. 10. 24. 1. Original 

 number 145. Collected 26th June, 1913, by Gilbert Ham- 

 mond. Presented by Oldrield Thomas. 



On laying out the fair series now available of A. palliata, 

 the general difference between the buffy-sided specimens 

 from Central America and the present more tawny-mantled 

 set from Ecuador becomes very evident. The buffy-ticked 

 back, tendency to have a yellow-tipped tail, and the cranial 

 points above mentioned are further indications of subspecitic 

 distinction. 



Callicebus personatus brunello, subsp. n. 



Among the Titi Monkeys in the British Museum which 

 have been referred to Callicebus personatus there appear to be 

 two different forms, one from the N.E. corner of Sao Paulo, no 

 doubt that which also occurs near Rio Janeiro itself, and 

 another from the State of Espiritu Santo, whence a good 

 series of it were sent by Mr. A. Robert. 



The original Callithrix personatus of Geoffroy was without 

 any more exact locality than " Bresil," and its description is 

 too brief to be distinctive, though the words " Pelage cendre'- 

 fauve " correspond better with the Espiritu Santo form than 

 with the more southern one. 



Apart from Humboldt, who merely reproduced Geoffroy 's 



