Charles Bonnet was a Genevan naturalist and philosophical writer. He is responsible for coining the term phyllotaxis to describe the arrangement of leaves on a plant. He was among the first to notice parthenogenetic reproduction in aphids and established that insects respired through their spiracles. He was among the first to use the term "evolution" in a biological context. Deaf from an early age, he also suffered from failing eyesight and had to make use of assistants in later life to help in his research.
Bonnet painted by Jens Juel, 1777.
Chain of being from Traité d'insectologie, 1745
Contemporary drawing of Bonnet's tomb in what was then the Parc des Plantes, now the Parc des Bastions. It was later removed, its whereabouts unknown. From the collections of the Bibliothèque des Genève.
Bust of Charles Bonnet by James Pradier, on display on the grounds of the Conservatory and Botanical Garden of the City of Geneva.
In botany, phyllotaxis or phyllotaxy is the arrangement of leaves on a plant stem. Phyllotactic spirals form a distinctive class of patterns in nature.
Crisscrossing spirals of Aloe polyphylla
Veronicastrum virginicum has whorls of leaves separated by long internodes.
Distichous leaf arrangement in Clivia
A Lithops species, showing its decussate growth in which a single pair of leaves is replaced at a time, leaving just one live active pair of leaves as the old pair withers
