Observationum botanicarum fasciculus primus

Romanus Adolf Hedwig (1772-1806) was the son of German bryologist Johann Hedwig, who settled in Leipzig as a professor of botany at the University and director of the botanical garden. Romanus studied at the University and became a professor of botany himself in 1801, shortly after his father's death (1799). One of only four of Johann's 15 children to survive him, Romanus carried on his father's herbarium, specializing in mosses; though it was sold at auction in 1810, much of the collection has been re-assembled at the Conservatoire et Jardin botaniques in Geneva.

The Observationum botanicarum was delivered as an academic oration and first published in February 1802 by the Leipzig printer Hirschfeld (ex officina Hirschfeldia) in 15 pages with no plates. This version is held by only one library in the U.S.: the National Agricultural Library. In May of the same year, a "trade edition" was published by a different printer (in bibliopolio [sic] Schaeferiano) in 20 pages, with 11 plates commissioned for the work. This edition is held by five libraries in the U.S.: the Smithsonian, Harvard's Botany Library, Michigan State University, Missouri Botanic Garden, and the New York Botanical Garden.

As the title indicates, the 20 pages seem to have been intended as the first part of a larger work, starting with the mosses and lower plants, but no evidence has been found to indicate that the work was ever continued. Hedwig contributed to Weber and Mohr's Beiträge zur Naturkunde (Kiel, 1805[-1806]) and published his greatest work, the Genera plantarum, in 1806. He died in the same year at the age of 34.