BOTANY St. Albans ; Aldbury and Ashridge Park, Tring. In the Lea district : Hatfield Park ; Digswell Park and Sherrards Park Wood near Welwyn ; and the Broxbourne Woods. On each of these occasions, except in 1896, the society had the benefit of the presence of either Dr. M. C. Cooke or Mr. George Massee, sometimes also with Mr. Worthington Smith and Dr. H. T. Wharton, who have furnished lists of the fungi for publication in the Transactions of the Society. From the year 1888 all the lists have been contributed by Mr. Massee. It is to these lists that our knowledge of the fungi of the county is almost entirely due, and they have furnished nearly every record here given, except the Uredineae and the Myxomycetes or those of Mycetozoa. The various groups of fungi will not here be treated in quite a uniform manner. A complete list of species of the Mycetozoa of the county is contributed by the Herts Natural History Society's recorder of this group, Mr. James Saunders, but of all the other fungi lists of the genera only are given, the number of species of each genus which have been found in Hertfordshire being denoted by a figure after its name, forming a census of the fungi at present known to occur in the county. From insufficient knowledge the Tuberaceas, Hysteriacea?, Ustilagineae, and Sphasropsideas are omitted, and so also are the microbes Schizomy- cetes and Saccharomycetes. This is not the place to treat of the classification or the morpho- logy of the fungi in general, but on account of the great interest attaching to the metamorphoses through which the Uredineae pass, a brief account of the life-cycle of these microscopic leaf-fungi is given in accord- ance with the views of their chief British investigator, Mr. Charles B. Plowright, whose nomenclature is followed. For the same reason the Mycetozoa are similarly treated (by Mr. Saunders), in this order Mr. Arthur Lister being the authority followed. In all the other groups the classification, nomenclature, and sequence of genera (and also of species when mentioned) are in accordance with Dr. M. C. Cooke's Handbook of British Fungi (1871), modified as to the grouping of the orders chiefly in accordance with his latest views as expressed in his Introduction to the Study of Fungi (1895). The fungi which are known to occur in Hertfordshire belong to the following orders (numbered) and larger divisions Basidiomycetes ( l " Hymenomycetes . . . . Mushroom-like fungi I 2. Gastromycetes .... Puff-ball fungi 3. Uredineae Rust fungi Ascomvcetes ( 4 " Venomycetes Capsular fungi I 5. Discomycetes Discoid fungi 6. Physomycetes Conjugating fungi 7. Hyphomycer.es .... Moulds 8. Myxomycetes or Mycetozoa Slime fungi The Hymenomycetes and Gastromycetes are the only orders of the division of the Basidiomycetes, and comprise all the fungi which have naked spores borne on short and thick supports called basidia. Nearly all the larger fungi which grow on the ground belong to this division,
