THE CHICAGO ACADEMY OF SCIENCES. 
14 
The waters of this lake fluctuated in depth, finally 
becoming so high that an outlet was effected to the north into the Snake 
19,000 square miles. 
The western lake, Lake Lahontan, did not attain the size of 
River. 
no 
uz. 
Yi lyjney 
GM YY” 
%: 
Y 
Yi 
Qe Yh 
UD 
‘42 
ofthe Colorado 
Oher fucific drainage 
Bus 

Fic. 5. 
showing Quaternary Lakes. 
Bull. U. S. Geol 
, 
The Great Basin of Utah 
Surv., No. 11, pl. 1. 
Lake Bonneville (reaching an area only of 9000 square miles) and 
Numerous smaller lakes also developed, most 
of which have long since disappeared. Great Salt Lake and Servier 
was without an outlet. 
