Title: Correspondence
Subjects: Correspondence, Botanical specimens, Euphorbiaceae, Pinaceae, Convovulaceae, Euphorbia
People: F. A. Wislizenus (1810-1889), George Engelmann (1809-1884), A. Grisebach (1814-1879), Asa Gray (1810-1888), Alexander Braun (1805-1877)