Arthur Henfrey was born at Aberdeen, in 1819, of English parents. He underwent the usual course of training for the medical profession at St Bartholomew's Hospital--becoming a member of the Royal College of Surgeons in 1843. In consequence of bronchial trouble, to which he eventually succumbed at the early age of 39, Henfrey never practised his profession. Compelled to a life of seclusion he at once turned to a scientific career and more particularly to the pursuit of botany. In 1847 he undertook the duties of Lecturer in Botany at St George's Hospital Medical School, where among his colleagues was Edwin Lankester, himself a redoubtable naturalist and the father of Sir Ray Lankester, the eminent zoologist of our own day.
Henfrey succeeded Edward Forbes as Professor of Botany in King's College, London, in 1852--a post which he held till his death. He was elected to the Fellowship of the Royal Society in the same year.
He died quite suddenly in 1859, at the house on Turnham Green, where he had resided for many years.
In order to understand the part played by Henfrey, it is necessary briefly to review the state of botany in the first half of the nineteenth century.
Linnaeus of course, botanically, the outstanding fact of the eighteenth century, was no exception to the dictum that "the evil that men do lives after them."
It was supposed that botany had reached its culminating point in Linnaeus and that improvement could only be made in details--elaborating and extending his system. As Sachs tells us in his _History_, the result was that "Botany ceased to be a science; even the describing of plants which Linnaeus had raised to an art became once more loose and negligent in the hands of his successors. Botany gradually degenerated under the influence of his authority into an insipid dilettantism--a dull occupation for plant collectors who called themselves systematists, in entire contravention of the meaning of the word."
This was written with especial reference to Germany, but it applied with no less force to our own country where the Linnaean idea had taken deep root and the Linnaean collections had found a sanctuary.
However, by 1840, a change was coming over the face of botany. Little as it can have been dreamt, the Golden Age was already beginning--destined in a relatively short time to transform the subject. This Golden Age was contemporaneous with, and immediately dependent on, the rise of a group of young botanists in the Fatherland, a group which included von Mohl, Schleiden, Hofmeister, Nägeli, Cohn and De Bary. Later it was reinforced by Sachs, who in addition to being a brilliant physiologist was a gifted writer who did much to establish scientific botany on a sound footing. It is impossible to overestimate the debt due to Sachs, particularly for his great _Textbook of Botany_, which at the right psychological moment brought the whole of the modern work between the covers of a single volume.