The first important paper dealing with the morphology of the hymenial structure in Fungi, is entitled, "On the Fructification of the Pileate and Clavate Tribes of the Hymenomycetous Fungi," Annals of Nat. Hist., 1838. Here is clearly demonstrated for the first time, the universal occurrence of basidia bearing spores at their summit, throughout the entire group of fungi known to-day as the Hymenomycetes, including Agaricaceae, Thelephoraceae, Clavariaceae, etc. This important discovery rendered possible the basis of a classification on morphological grounds, which holds good at the present day. A careful study of the text and illustrations demonstrates the fact that Berkeley was perfectly well acquainted with all the essential details of the hymenium, many of which have been repeatedly rediscovered and described under new names, in ignorance of the fact that such structures had previously been equally well described.
Berkeley continued his investigations on the structure of the hymenium, and his next paper, entitled "Sur la fructification des genres Lycoperdon, Phallus et de quelques autres genres voisins," in Annal. Sci. Nat. Ser. 2, vol. xii. (1839), demonstrated the universal presence of basidia bearing spores at their summit in the family now known as the Gasteromycetes. This research on the part of Berkeley led to the universal adoption of the two primary divisions of the Fungi; Basidiomycetes, having the spores borne at the apex of a basidium; and Ascomycetes, having the spores produced within specialised sacs, or asci.
In 1857 the Introduction to Cryptogamic Botany appeared, which remained for many years the standard work on the subject. This was followed in 1860 by Outlines of British Mycology, a book profusely illustrated with coloured plates, and intended more especially for the beginner in the study of Mycology.
Just over 400 separate papers dealing with fungi are listed under Berkeley's name alone, in addition to numerous others, where he worked in collaboration with C. E. Broome, Dr M. C. Cooke, Rev. M. A. Curtis, and others.
Plant Pathology.
At the present day Berkeley is best known as a systematist, which of itself alone is sufficient to retain his name for all time in the front rank of mycologists, but when the history of Plant Pathology is elaborated, Berkeley's name will undoubtedly stand out more prominently than that of any other individual. In fact, it is not saying too much to pronounce Berkeley as the originator and founder of Plant Pathology. He was not the first to investigate plant diseases caused by fungi, but he was undoubtedly the first to recognise the significance of the subject, and its great importance from an economic standpoint. His investigation of the potato murrain, written in 1846, cleared the air of all kinds of wild theories as to its origin, and showed it to be undoubtedly caused by the fungus now known as Phytophthora infestans, whose life-history he carefully worked out. Then followed a similar investigation of the vine-mildew, and a series of researches on diseases of plants published in the Gardeners' Chronicle dating from 1854 to 1880. It was in these numerous communications that the science of Plant Pathology was firmly established and propounded. The article "On the Diseases of Plants" was contributed to the Cyclopaedia of Agriculture by Berkeley.
In 1879 he unconditionally presented his mycological herbarium to Kew. This collection contained 10,000 species, of which 5000 were types of Berkeley's own species, in addition to numerous co-types from Montagne, Schweinitz, Fries, Cooke and other contemporaneous mycologists. Hence Kew is, and must for ever remain, the Mecca of mycologists from all parts of the world.
Berkeley was a man of great refinement, and an excellent classical scholar. His tall commanding figure and grand head with flowing white hair, as I knew him late in life, could not fail to arrest attention. Unobtrusive and by no means ambitious, and too enthusiastic to be self-seeking, Berkeley was tardily promoted to the Honorary Fellowship of his College, and elected a Fellow of the Royal Society at the age of 76. In 1876 a Civil List Pension of £100 per annum was awarded, for his services to botany with especial reference to his investigations on the diseases of plants.