28 THE ESSEX NATURALIST. Lecanora atra, Ach. On brick wall, Uplands, Loughton: sparingly fertile. Lecanora Hageni, Ach. On willow trunk, Roding bank between Loughton and Buckhurst Hill: fertile. Lecanora polytropa, Schaer. On flints, Great and Little Monk Woods: fertile. Lecanora calcarea, Sommerf. On stonework of Epping Old Church; ditto, Nazing Church: sparingly fertile. Thelotrema lepadinum, Ach., On fallen hornbeam trunk, Green Ride to S. of Great Monk Wood: fertile. Cladonia uncialis, Web. form bolacina, Nyl. On heathy ground by Green Ride to E. of Great Monk Wood: sterile. Cladonia digitata, Hoffm. On banks, Jack's Hill; ditto, by Green Ride to E. of Great Monk Wood: fertile. Lecidea Friesii. Ach. On oak trunk, N. of Great Monk Wood: sterile. Lecidea ochracea, Wedd. On cement, Jack's Hill, Theydon: fertile. Lecidea contigua, Fr. On brick wall-tops, Theydon Bois railway station, Epping town; etc.: fertile. Verrucaria rupestris, Schrad. On limestone coping of wall, Loughton Church; on tombstone, Epping Old Church; etc.: fertile. Since the appearance of our earlier papers, the synonymy of the Class Lichenes has undergone extensive modification owing to the publication of Miss A. Lorrain Smith's exhaustive Monograph2 by the British Museum authorities. It appears advisable, therefore, to bring our previous lists, so far as thereby affected, into line with the new nomenclature. This is as follows:— Calicium melanophaeum, Ach. is now Chaenotheca melanophaea, Zwackh. Do., var. ferrugineum, Schaer, is now Do., var. ferruginea, A. L. Sm. 2 A Monograph of the British Lichens, part i., and edition, 191.