Letters (23) written to Muhlenberg, owned by American Philosophical Society. The Denke letters were photostated for C. Earle Smith, Jr. for his research on the historical plant collections in the Academy, and archived by him in 1957. Fragmentary because Smith removed the various lists of plants to be kept with the Academy's herbarium. Also in Coll. 910 are an Index and a Supplement, 1797-99, to Kramsch's Flora Nazarethana. Another two volumes, unsigned, but identified as the hand of C. Denke by C. Earle Smith, Jr. These volumes are possibly new compilations or classroom texts, one about animals, the other based on Linne's Philosophia Botanica, 1751. The latter is enlarged to cover many more species and with descriptive material not included in Linne.