EXPLORATIONS AND SURVEYS FOR A RAILROAD ROUTE FROM THE MISSISSIPPI RIVER TO THE PACIFIC OCEAN. 
WAR DEPARTMENT. 
BIRDS'. 
BY SPENCER F. BAIRD. 
ASSISTANT SECRETARY SMITHSONIAN INSTITUTION. 
WITH THE CO-OPERATION OP 
JOHN CASSIN AND GEORGE N. LAWRENCE. 
WASHINGTON, D. C. 
1 8 5 8. 
