392 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. 
In this region, as in general in every considerable widenings of the 
Cordillera, the grouped summits do not follow the principal axes in 
uniform and parallel directions, and he remarked that the general 
disposition of the Andes in this latitude is well worth the attention 
of geologists. From where the Cordilleras unite in the knot of Cuzco 
(Vilcanota) their direction is N. 80° W. He calls attention to the 
fact that the direction of the coast follows these changes, and remarks 
that the parallelism between the coast and the Cordilleras of the 
Andes is a phenomenon the more worthy of attention as it occurs in 
several parts of the globe where the mountains do not in the same 
manner form the shore. 
DESCRIPTION BY RAIMONDI. 
It is to be regretted that Raimondi did not publish a description of 
the Andes. However, his writings contain much information, and 
in his edited notes published in the chapter “Apuntes Orograficos,” 
in Volume IV of El Peru there is a partial description of the 
Cordilleras. He adopted the nomenclature of Humboldt. The 
Andes is used as a general term for the whole mountain system, 
and the various branches are spoken of as “ Cordilleras.” The 
branch to the east of Lake Titicaca he called the “ Cordillera Ori- 
ental” and the one to the west the “ Cordillera Occidental.” The 
union of these branches to the north of Lake Titicaca he calls the 
“Knot of Vilcanota,” taking the name from a snow-capped peak. 
From this knot northward he recognized three branches instead ¢£- 
the two somewhat vaguely described by Humboldt. The Cordillera 
Occidental follows the direction of the coast. The Cordillera Cen- 
tral separates the valleys of the Apurimac and the Vilcanota or 
Urubamba rivers, while the Cordillera Oriental separates the inter- — 
Andean region from the forest region of the interior. These three 
Cordilleras unite in the Knot of Cerro de Pasco, from which point 
northward three branches diverge. The Cordillera Occidental for a 
portion of its way is divided into two, the western of which is known 
as the “ Cordillera Negra” (Black Cordillera) and the eastern or 
main one takes in that region the name “ Cordillera Blanca ” (White 
Cordillera) because of its snow-covered peaks. The Cordillera Cen- 
tral separates the Maranon and Huallaga rivers, while the Cordillera 
Oriental separates the Huallaga from the Pachitea and Ucayali. 
The Cordillera Central describes a curve, and is cut by the Maranon 
at the falls of Manseriche. The Cordillera Oriental lowers, and is cut 
by the Huallaga at the Falls of Aguirre and then runs in a north- 
west direction and joins the Cordillera Central. Humboldt states 
that it dies out in latitude 6° 15’. With this exception, it will be seen 
that in the northern part of Peru the description by Raimondi does 
