specimens are in St. Petersburg. Some of the specimens include those collected by Humboldt.

Humboldt notes that as a young man, he was unable to identify plants using Willdenow's Flora Berolinensis which was published from 1803 to 1812. In it he had described nearly 80 species, with hand-coloured copper engravings of plants. In 1804 Willdenow wrote a self-study textbook of botany. Humboldt visited Willdenow, often without an appointment and found him to be a kindred soul only four years older and in three weeks he became an enthusiastic