EXPLORATIONS AND SURVEYS FOR A RAILROAD ROUTE FROM THE MISSISSIPPI RIVER TO THE PACIFIC OCEAN. 
WAR DEPARTMENT, 
REPORT 
ON THE 
BOTANY OF TEE EXPEDITION: 
BY • 
JOHN TORREY AND ASA GRAY. 
ROUTE ON THE FORTY-FIRST PARALLEL OF NORTH LATITUDE, UNDER THE COMMAND OF LIEUT. E. G. 
BECKWITH, THIRD ARTILLERY; 
AND 
ROUTE NEAR THE THIRTY-EIGHTH AND THIRTY-NINTH PARALLELS OF NORTH LATITUDE, UNDER THE 
COMMAND OF CAPT. J. W. GUNNISON, CORPS OF TOPOGRAPHICAL ENGINEERS. 
