Opportunity alone was required by Berkeley, and such opportunity was readily afforded by Sir W. J. Hooker, who placed unreservedly in Berkeley's hands the various collections of exotic fungi received at Kew from time to time. This practice was continued by the two succeeding Directors at Kew, Sir Joseph Dalton Hooker and Sir William Thiselton-Dyer. Such unrivalled opportunities were utilised to the fullest extent by Berkeley, who soon manifested by his treatment of the material placed in his hands a thorough grasp of the subject, and for nearly half a century practically all collections of exotic fungi passed through Berkeley's hands. During this period 6000 new species were described, and in numerous instances illustrated, including many new genera from all parts of the world, arctic, antarctic, tropical and temperate. Botanists were now enabled, for the first time, to grasp the true significance of the fungus-flora of the world, which numerically ranks next to Phanerogams, and which was shown to exercise an influence on life on the globe in general, not realised before Berkeley's time. The better known European genera of fungi, many of which appeared to be sharply defined, and by some mycologists considered to be of ordinal importance, could now be estimated at their true value and relegated to their true position in the scheme of classification rendered possible by a good knowledge of the range of structure presented by the fungi of the world at large. As regards geographical distribution, Berkeley repeatedly emphasized the fact that the fungi are more cosmopolitan than any other known group of plants, and that their abundance at any place during a given period was almost entirely dependent on conditions favouring the development of the higher forms of plant life, fungi only following in the wake of such, and never posing as pioneers, on account of the nature of their food. Amongst the numerous novel types of extra-European fungi described by Berkeley, it is somewhat difficult to indicate briefly even a few of the most striking forms. Perhaps his genus _Broomeia_ stands out pre-eminent. It belongs to the puffball group of fungi, and is unique in that family--the Gasteromycetaceae--in having numerous individuals springing from, and imbedded in a common sterile base or stroma. It is a native of the Cape of Good Hope. The following is Berkeley's dedication of this genus to his friend and co-worker, C. E. Broome, M.A., of Bath. "Nomen dedi in honorem amicissimi, C. E. Broome, armigeri, Tuberacearum Anglicarum accuratissimi indagatoris, cujus pene solius laboribus extant hodie viginti species indigenae fungorum hypogaeorum." _Broomeia congregata_ Berk., is described and figured in Hooker's _London Journal of Botany_, 1844. Certain club-shaped fungi parasitic on caterpillars, belonging to the genus _Cordyceps_, occurring on buried caterpillars in New Zealand, are the giants of their tribe, measuring up to eighteen inches in length.