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 BOTANY recorded by Dr. M. C. Cooke as P. bullatum (on twigs of Rosa canina at Barnet), by Mr. E. M. Chater as P. mucronatum (on rose-leaves at Watford), and by Mr. J. W. Walker as Lecythea rosce (on roses in the neighbourhood of Watford). Cluster-cups are pests, injuring the plant on which they grow, and we have one instance of the apparent extinction by their means of a rare plant in a locality in which it had long been established. Anemone ranunculoides formerly grew in the corner of a field at Abbot's Langley. In May, 1 8 8 1, the present writer saw a few plants there with leaves thickened and some also elongated by the hyphas of JEcidium punctatum. The plants looked far from healthy, and on a visit to the spot some years later not one was to be found. Very little is known of the distribution of the leaf-fungi in Hert- fordshire ; in fact nearly all our records relate to the south-west of the county, chiefly to the neighbourhood of Watford and St. Albans. The eighteen species of Uredines recorded in Pryor's Flora are now however brought up to forty, all of which are found in the neighbourhood of Watford. There is still a wide field in the county for further investiga- tion of this interesting group of plant-parasites. 4. PYRENOMYCETES Uncinula. . I Nectria. . . I Dothidea. . i Sphaeria ... 3 Rhytisma. . 2 Xylaria ... 3 Microstoma. . I Sphxrella. . i Hypochrea. . I Daldinea. . i Valsa. ... 4 Venturia. . . i Hypomyces. . I Hypoxylon. . i Bysossphaeria. I The rarer species are Daldinea concentrica, Microstoma album, Bysos- sphceria aquilla, and Sphcerella fragrance, from Cassiobury Park, Valsa corylina from Hatfield Park, and Venturia glomerata recorded by Dr. Cooke in Grevillea (vol. iii. p. 69) as found by him at Barnet in 1874. 5. DlSCOMYCETES Morchella. . i Geoglossum. . i Helotium. . 5 Phacidium. . 2 Helvella I Peziza. . .10 Bulgaria I This is an interesting order, comprising several esculent and some very pretty species. Of the former we have only the common morel (Morchella esculenta] and the pallid helvella (He he I la crispa] ; of the latter we have several species of Peziza, the prettiest being the common P. aurantia and P. virgmea, one of a brilliant orange and the other of a pure white colour, the rather local carmine peziza (P. coccinea) found in a wood near Watford, and the very rare P. luteo-nitens detected in 1894 on the Chalk slope between Aldbury and Ashridge Park. The colour of this is a bright orange-yellow. Another rare species, P. ampliata, was found in Digswell Park in 1893. 6. PHYSOMYCETES The only species of this order we have on record are Cystopus can- 75