Mrs. Calvert, a naturalist and zoologist accompanied her husband P. P. Calvert to Costa Rica in 1909 and 1910 and while there took the photographs used by the Calverts in their book entitled A Year of Costa Rican Natural History. Two volumes of loose leaf notebooks contain 104 photographs of plants which were identified by Adolfo Tonduz, a botanist of the Museu Nacional at San José and Henry Francois Pittier. The photographs are mounted on individual sheets with typewritten descriptions by Mrs. Calvert. On May 22, 1961, she reported that she had prepared three copies one for the University of Pennsylvania, and one for the Academy and the third for herself.