234 MR. OLDFIELD THOMAS OX THE MAMMALS [NoV. 3, 



Cuyabd is on the river level, and the country towards Chapada 

 is all at the same low altitude until the abrupt rise of the plateau 

 edge is reached, comparatively close to Santa Anna. 



Mr. Robert has discovered a considerable number of new and 

 interesting species, of which the most notable is the Wild Dog 

 (PI. XXVII.), which I have named in honour of the late Mr. Percy 

 Sladen. 



1, Cebus azar^ Rengg. 



c?. 1022, 1041, 1083, 1085, 1093, 1188, 1143, 1171, 1174, 

 1196, 1197, 1198, 1208. 



2. 1045, 1082, 1086, 1094, 1104, 1105, 1152, 1175, 1176. 



In the absence of any certainty that Spix's name Cehus lihidi- 

 nosibs (type locality, Rio San Francisco) really belongs to this 

 monkey, I use that of Rengger, which antedates Geoffrey's 

 C. elegans by many years. 



This fine series emphasizes the difficulty of working out 

 members of the present genus, for there is considerable variation 

 both in the general colour, in the relative distribution of black 

 and yellow on the head, and in the length and development of 

 the temporal tufts. 



2. Actus azar^ Humb. 

 Nyctipithecibs azarce auct. 

 $.1150. 28 September, 1902. 



■ 3. Callithrix* melaxura Geoff. 



6. 1130. 

 $. 1132. 



4. HisTioTus velatus Geoff. 

 ?. 1186. 



5. Micronycteris megalotis Gray 

 ?. 1014, 1015. 



G. Hemiderma perspicillatum Linn. 



cT. 1063. 



$. 1012, 1013. 



7. LONCHOGLOSSA CAUDIFERA Geoff. 



c?. 1000, 1001, 1002. 

 $. 999, nil. 



8. Artibeus planirostris Spix. 

 6. 1089. 



* For the use of Callithrix instead of Hapale, see Ann. Mas. N. H. (7) xii. 

 p. ido (1903). 



