John Stevens Henslow (1796–1861) was a botanist and geologist. As teacher, mentor and friend to Charles Darwin, it was his introduction that secured for Darwin the post of naturalist on the voyage of the Beagle. While Professor of Botany, Henslow established the Cambridge University Botanic Garden as a resource for teaching and research. Students were encouraged to examine plant specimens carefully, and to record the characteristics of their structures. Henslow would have known how daunting they found the task of becoming proficient with botanical vocabulary, and produced this volume to provide a secure foundation for scientific investigations. This meticulous glossary, originally published as a single volume in 1857 but drawing on contributions he made earlier to issues of The Botanist and Maund's Botanic Garden, is a testament to Henslow's scholarship. It is liberally illustrated with delightful woodcuts that clarify the meaning of selected terms. Darwin's mentor published this illustrated botanical glossary in 1857 to provide a secure foundation for scientific investigations.