The Mulford Expedition of 1921–1922 was organized by Henry Hurd Rusby to explore the Amazon Valley from the headwaters of the Quime River in Bolivia to the mouth of the Amazon in Brazil. Dr. Rusby, then 70 years old, was a well-known explorer, a professor at Colombia University, and a member of the New York Botanical Garden staff. Funding was obtained from the H. K. Mulford Company. To assist him in collecting and handling plant specimens, Rusby hired Dr. Orland E. White, of Brooklyn Botanic Garden.
The expedition arrived in Bolivia in July 1921 and began collecting high in the Andes, just south of La Paz. Using balsa-wood rafts, they moved down the Bopi River, stopping for weeks at a time to collect in Huacho and Rurrenabaque. In December, Rusby was forced to leave the expedition due to ill health, traveling alone down the river until he was rescued by a government patrol boat. Before he left, he hired Martin Cardenas, then a student, to assist with collecting. White and Cardenas continued collecting in the lowlands of Eastern Bolivia, making extensive collections near Tumupasa, Ixiamas, Lago Rogagua, Ivon, and Cachuela Esperanza.
The botanists never reached the Amazon, but headed home from Cachuela Esperanza, Bolivia, in mid-March, 1922, after eight months in the field. They returned with about 2,400 collections representing over 1,500 species. Their collections were especially rich in orchids, economic plants, and seeds.
Rusby worked through almost all the specimens himself, identifying and describing six new genera and 257 new species.
The main collections for the expedition, including the holotypes, are at the New York Botanical Garden. A nearly complete set of specimens, including isotypes, is in the Brooklyn Botanic Garden Herbarium. Partial sets of duplicate specimens from the Mulford Expedition were distributed to the U.S. Department of Agriculture, now at the Smithsonian, the Gray Herbarium, the Ames Economic Herbarium, and the Academy of Natural Sciences in Philadelphia. Small sets of a few specimens were sent to Chicago's Field Museum, the Royal Botanic Garden, Kew, Berlin Botanic Garden, and the Herbario Nacional de Bolivia (now at the Herbario Nacional Forestal Dr. Martin Cardenas).
Rusby's "Report of Work on the Mulford Biological Exploration of 1921–22" was published in the Journal of the New York Botanical Garden 23(272): 101–111, in August 1922.
Rusby described a few species in "New Species of Trees of Medicinal Interest from Bolivia" in The Bulletin of the Torrey Botanical Club 49: 259–264, in September 1922 and published a paper on the medicinal uses of the species in the Journal of the American Pharmaceutical Association in October 1922.
Most of the new species were described by Rusby in "Descriptions of New Genera and Species of Plants Collected on the Mulford Biologial Exploration of the Amazon Valley, 1921–1922," published in the Memoirs of the New York Botanical Garden 7: 205–387, in March 1927.
O.E. White's "Botanical Explorations in Bolivia" was published in Brooklyn Botanic Garden Record 11(3): 93–105, in July 1922.
White's "El Monte" appeared in Brooklyn Botanic Garden Leaflets 11(8), in October 1923.
White's 'Forest of the Rio Beni Basin of Bolivia" appeared in Cornell Forester 6: 16–20, in May 1926.
Gordon MacCreagh, an anthropologist with the expedition, wrote a witty and sarcastic account of the Mulford Expedition in White Waters and Black, one of the best scientific travelogues ever written. Don't miss his accounts of the "distinguished director," Rusby, and "distinguished botanist," White. Originally published in 1926, it was later reprinted in 1961 and in 1987 but is currently out of print.
Rusby's autobiography, Jungle Memories, was published in 1933.