List of Plants Collected by W. P. Cottam in the vicinity of Tuweep Valley and Mount Trumbull, Mohave County, Arizona
Cottam WP. 1942. List of Plants Collected by W. P. Cottam in the vicinity of Tuweep Valley and Mount Trumbull, Mohave County, Arizona. National Park Service
The list and accompanying correspondence refer to a set of 84 mounted plant specimens Dr. Cottam collected along the rim of the canyon at Tuweep Point and on Mt. Trumbull, and donated to the Grand Canyon National Park herbarium. The list has family and species names, and location for each specimen