Full title: "Pflanzen-Kalender oder Versuch einer Anweisung welche Pflanzen man in jedem Monat in ihrer Blüthe finden könne und auf welchem Standorte. Zweyte vermehrte Auflage." This enlarged edition, is split into two volumes. It is said that when when Heyne began to practice botany, he felt the lack of a book from which one could see the flowering times of numerous plants - and wrote the book himself. Both volumes in hardback with faux leather paper covered boards. These are a little rubbed to the corners and edges, with some loss. There are burgundy leather labels attached to the spine of each volume, giving titles in gilt. gilt decoration to the top and bottom of each volume. The first volume has a guide to the study of botany by Dr. Schwägrichen and then covers the period January to June and the second, July to December. The first edition was in 1804, and was followed by this expanded edition in 1806. LII, 1-164., 165-404 pages. This is printed in a strange way. The introduction is printed in the normal way, but then the actual pages of the book, are printed in the normal way, but have a blank page inserted in between each leaf. This is not numbered or part of the pagination. The printed pages of volume one are moderately to heavily foxed, and we suspect that this was printed on poor quality paper, and that the pages between were almost a blotting sheet. Volume two has mild to moderate foxing. The pages are otherwise clean, except for some ink marks to page v. (Text is still legible). Some charts and plans as part of the text. To the rear as some tables which show the six orders of plants (classification by the Linnean system) and a description of how you can tell the plants in each. There are no illustrations in the work (nor were there intended to be - so the work is complete). This seems to be a very scarce work, and we can find only one copy of the first edition, and one incomplete copy of the second for sale. Our copy conforms with OCLC: 16522145 There are only four library holdings. 2 in the USA, Nijmegen and Kew in England. (Surprisingly no German library holdings).