Recommends Wyman’s short notice ["Report on Dr Jeffries Wyman’s experiment on the cause of contractility in vegetable tissues"] in the Proceedings of the American Academy of Arts and Sciences 3 (1852–7): 167.

Fertile flowers of violets, except Viola tricolor, require insect visits.

Discusses the contraction of hygroscopic bundles in seed-pods,

and a paper by Hugo von Mohl ["Über dimorphe Blüthen", Bot. Ztg. (1863): 309–15, 321–8] in which he discusses Oxalis and determines that Fumaria is a necessarily self-fertilising plant.