8 BULLETIN 117, UNITED STATES NATIONAL MUSEUM. 



altitude 12,500 feet) is of special importance. This zone has been 

 previously explored in Peru only in the district about Maraynioc in 

 the Eastern Cordillera somewhat north of the latitude of Lima, where 

 von Tschudi, Jelski, and Kalinowski secured a surprising number of 

 distinct new forms. The rainfall which produces the forest character- 

 izing the humid Temperate Zone is also, in a measure, responsible for 

 our ignorance of its life. The rain creates not only forests, but also 

 rivers, and the river valleys form the natural sites for the trails which 

 connect the highlands and lowlands. When the collector, in following 

 these trails, reaches the region of Temperate Zone forests, his path is 

 far below them and he thus passes under a zone of exceptional interest- 

 I had this experience in the Eastern Andes of Colombia between 

 Bogota and Villavicencio ;^ while Kalinowski, who collected during 

 several years in the Urubamba region, appears not to have worked in 

 the forests of the humid Temperate Zone, though he lived within a 

 few miles of them. 



The authorities of the Yale University-National Geographic Society 

 having honored me by a request to report upon Heller's collection of 

 birds, 1 decided to alter an itinerary already made for a reconnaissance 

 in. South America, on which I was to start four days after this request 

 was received, to permit me to make a hurried journej^ down the Uru- 

 bamba Valley as far as Santa Ana. This was done under the auspices 

 of the institutions just named. 



Leaving Cuzco with our pack animals on July 1, vre retm^ned to 

 that city on July 24, making meanwhile 13 camps in localities rep- 

 resenting all the faunal areas of the region, except the humid Tem- 

 perate and humid Tropical Zones, which the very limited tim.e at my 

 command prevented me from visiting. Unfortunately it had not 

 been possible to make a critical examination of Heller's collections 

 before leaving, or to examine his field notes, nevertheless I realize 

 that without this personal experience, brief as it was, I should not be 

 in a position to prepare even the provisional discussion of the faunal 

 problems of this region which is presented beyond. 



I was accompanied on this short expedition by that veteran col- 

 lector, George K. Cherrie, and by my son, Frank M. Chapman, Jr., 

 and at Tirapata we were joined by Harry Watkins, a resident natu- 

 ralist who for some years before had been securing birds for the 

 American Museum. Cherrie was the same invaluable lieutenant that 

 he has been on former occasions, and Watkins proved an efficient aid. 

 With the balance left from the appropriation made for this expedition 

 by the National Geographic Society, Watkins was later employed to 

 make collections at La liaya and in tlie Cuzco district in April, 1917. 



Cordial acknowledgement for assistance in the preparation of the 

 paper is due my staff associates, Mrs. A. K. Eraser, Mr. Ludlow 



« See Bull. Amer. Mus. Nat. Hist., vol. 36, 1917, p. 55. 



