Anne Barnard,her life and contribution to Curtis's Botanical Magazine

Anne Barnard (23 June 1833–19 January 1899), née Henslow, made around 125 illustrations for Curtis's Botanical Magazine, during the editorship of J.D. Hooker. Her life and botanical works are reviewed here, and examples of her original paintings are given.     

Botanical expeditions of The New York Botanical Garden

A list is given of the botanical expeditions undertaken by staff members, graduate students, and close collaborators of The New York Botanical Garden from 1897 to 1994.     

Botanical ratchets

Ratcheting surfaces are a common motif in nature and appear in plant awns and grasses. They are known to proffer selective advantages for seed dispersion and burial. In two simple model experiments, we show that these anisotropically toothed surfaces naturally serve as motion rectifiers and generically move in a unidirectional manner, when subjected to temporally and spatially symmetric excitations of various origins. Using a combination of theory and experiment, we show that a linear relationship between awn length and ratchet efficiency holds under biologically relevant conditions. Grass awns can thus efficiently transform non-equilibrium environmental stresses from such sources as humidity variations into useful work and directed motion using their length as a fluctuation amplifier, yielding a selective advantage to these organelles in many plant species.