2oo FIELD MUSEUM OF NATURAL HISTORY ZOOLOGY, VOL. X. 



the Amazon near Santarem for a time, the whole party returned directly 

 to the United States. 



Notwithstanding the difficult climatic conditions and the limited 

 time which was available for actual field work the collections obtained 

 are of considerable size and importance, especially in view of the very 

 small representation of the fauna of the region traversed which was 

 previously possessed by North American museums. According to the 

 generous plan of Mr. Collins and Mr. Day these collections are to be 

 divided equally by the American Museum of Natural History and the 

 Field Museum of Natural History, the types of new birds remaining 

 with the New York institution and those of new mammals with the 

 Field Museum. 



The collection of mammals numbers some 325 specimens belonging 

 to 41 species and subspecies, of which four are new. In the brief 

 account of this collection which follows, I am indebted to Mr. Collins 

 for the notes on the hunting of guanacos and vicugnas. 



Martnosa elegans venusta Thomas. MOUSE OPOSSUM. 



Four specimens, Parotani. 



These topotypes are welcome additions to the collection of the Field 

 Museum, as of course they would be to any other. An interesting 

 character shown by two of them which are mature is a rather definite 

 dark spot occupying a considerable space on the side just behind the 

 shoulder. This is colored like the dark dorsal area and forms an inter- 

 ruption in the lower half of the lighter lateral area which in its upper 

 half separates this dark spot from the dorsal area. 



Bradypus tridactylus Linnaeus. THREE-TOED SLOTH. 



Three specimens, Santarem, Brazil. Collected by G. K. Cherrie. 



Hippocamelus antisiensis D'Orbigny. PERUVIAN GUEMAL. 



One specimen, Pampa de Arrieros, Peru. 



This is an immature male with milk dentition and short, stubby 

 horns. The pelage is somewhat worn but in general the hairs of the body 

 have buffy tips producing a rather pallid effect which is sharply con- 

 trasted with a dark blackish brown area on the back and rump just 

 anterior to the base of the tail. The tail itself is entirely white both 

 above and below and the white areas on the inner sides of the legs 

 extend to the hoofs. The dark facial markings, so well developed in 

 the Chilian H. bisulcus, are reduced to brownish patches over the eyes. 



This species was found up to an altitude of 13,000 feet, in general 

 ranging somewhat lower than the guanaco and vicugna. 



