U. 8. GEOGRAPHICAL SURVEYS WEST OF THE ONE HUNDREDTH MERIDIAN, FIRST 

 LIEUT. GEO. M. WHEELER, CORPS OF ENGINEERS, V. S. ARMY, IN CHARGE. 



REPORTS 



UPON 



THE BOTANICAL COLLECTIONS MADE IN PORTIONS OF NEVADA, UTAH, 

 CALIFORNIA, COLORADO, NEW MEXICO, AND ARIZONA, 



DUKLNG 



THE YEARS 1871, 1872, 1873, 1874, AND 1875. 



J. T. ROTHROCK, 



LATE A.. J^. SUB&BOST, XT. S. -AJRMY, 



SURGEON AND BOTANIST TO THE EXPEDITIONS OF 1873, 1874, AND 1875, AND NO"W PEOFESSOB 

 OF BOTANY IN THE UNIVERSITY OF PENNSYLVANIA, PHILADELPHIA, PA. ; 



AND THE FOLLOWING SCIENTISTS: 



SEKENO "WATSON, Cambridge, Mass. 

 GEOEGE ENGELMANN, M. D., St. Louis, Mo. 

 Prof. THOS. C. POETEE, Easton, Penn. 

 M. S. BEBB, Fountaindale, III. 

 ■WILLIAM BOOTT, BOSTON, MASS. 



GEOEGE VASEY, M. D., Agricultural Department, 



Washington, D. C. 

 Prof. D. C. EATON. Yale College, New Haven, Conn. 

 THOS. P. JAMES. Cambridge, Mass. 

 Prof. EDWARD TUCKERMAN, Amherst, Mass. 



IN FOUR CHAPTERS AND AN APPENDIX. 



ILLUSTRATED BY THIRTY PLATES AND ONE "WOODCUT. 



