Bowman — Geologic Relations of the Cuzco Remains. 311 



the bluff was an earthy coating deposited from the clouds of 

 dust raised by the feet of passing nocks and caravans. The 

 same gray-yellow appearance is exhibited upon all surfaces not 

 recently eroded. Upon removing the thin surface of such a 

 bluff one comes upon what might be called an under surface 

 somewhat like the under layer of skin on the human body and 

 upon or in this are countless hosts of fungi. Their branching 

 filaments or hyphae ramify through every pore ; by scraping 

 away the surface carefully one may exhibit a great area of 

 fungous-covered gravel. Beyond the outer film of material 



Fig. 8. 





Flat-topped, spur 







J 

 2( 



5 



4q° ^\ 



„ \"^^^ Highest alluvial grade 



>o' \ ^~~~~- ■ — - — " 



Y^- ^ First inner valley 



V ~-^^ '___ 









''' iq° 



T 7 \ \ ~Z^^ 



\ Second inner vol ley .^rvvv^ 

 Vertebrate r"mams\ x ' ^v\\\^' 



>^ 



39° 



r 68" J ]\ ^_-^"" _-^#^ 





31" 



V*l— — — ' 



. 



Fig. 8.* Topographic profile of ravine in which the vertebrate remains 

 were found. Compare with figs. 1, 4, 7, and 9. Scale : 1 inch = 200 feet, 

 vertical and horizontal. Shaded area represents bed rock exposed in tribu- 

 tary ravine. Degrees indicate declivity of ravine slopes at different eleva- 

 tions. 



one comes in turn upon the yellow unmodified gravel free 

 from dust and fungi. The linear distance from the face of 

 the bluff to the undisturbed material is never more than two 

 or three inches and generally but a half inch to an inch. 



The structure of the main mass of material in which the 

 bones were deposited may be observed in a ravine but fifty 

 feet west of the bone locality. The unbroken character of the 

 mass, its stratified condition, the fact that it lies as it was 

 deposited with moderate inclination of the material down- 

 valley, its smooth upper surface (fig. 1), its compact condition, 

 the entire absence of recent material within the body of the 

 gravel, — all these are features easy of observation and about 

 which it would seem there could never be any question either 

 as regards the facts or their interpretation. 



Across the ravine from the bone locality a tributary gully 

 extends far into the undisturbed gravels (fig. 9) ; the coarse- 

 ness of the material, its degree of stratification, and its angle 



* For figures 1-7 inclusive see preceding article. 



