Photostatic copies of proof sheets of Barton's “Prodromis Florae Pennsylvanicae” pages 78, 81, 83, 86, 115-122. Also proof sheets for The Elements of Botany, second edition, 1812, pages 25 and 32 with preface page xvii. These are accompanied by Mrs. Delafield's notes explaining her reasons for taking the position that the materials was never published. Another statement by Mrs. Delafield of the finding of the papers in 1936 and a list of items from Mrs. Delafield's Barton collection which were loaned to F. W. Pennell for an exhibit at the American Philosophical Society in 1941; Barton's prospectus addressed to the authorities of the University of Pennsylvania explaining his course of lectures in Materia Medica and various letters written to Barton are included here. Biographical items include news clippings about the man and a statement by F. W. Pennell as to the final disposition of the Barton herbarium.